Blog posts tagged with 'peter wilson'

On Friday, 16th December 2011 a small group gathered around the XJ13 at Jaguar Heritage to mark the launch of Peter Wilson's book, "XJ13 - The definitive story of the Jaguar Le Mans car and the V12 engine that powered it".

This was no ordinary gathering, as those present included many surviving members of the team that were originally involved in the original XJ13 car as well as the development of the engine that powered it. Those present included Norman Dewis, George Buck, Frank Philpott, Jim Eastick, Ron Greves, Mike Kimberley, Roger Shelbourne, Robert Berry, Peter Taylor and Peter Wilson himself.

Click the images below to see videos and more detail of the proceedings

The videos include introductions by Tony Duckhouse (on behalf of Jaguar Heritage), Paul Skilleter (renowned Jaguar author and publisher) and further insights by Mike Kimberley (XJ13 Project Manager - later to join Colin Chapman and become CEO of Group Lotus):

More details of the book itself are available from Paul Skilleter Books or the Jaguar Clubs of North America.

As the build of the "trial" all-steel monocoque/chassis progresses, I wanted to consider the materials that should be used for construction of the component parts of my final version. Jaguar themselves went through a similar exercise in 1964 when the XJ13 had reached an advanced design stage.

Before then, in the few years leading up to 1964, various studies/reports were made on things such as the shape of the overall body, the design of the underlying chassis structure and suspension design. One, quite advanced, design was for a rather more integrated monocoque design as shown in the following sketch from the November of 1963:

Early monocoque design for the XJ13.
© Image - reproduced with permission.

However, the above design was not progressed further and, instead, a separate monocoque/chassis unit was developed which was to be clothed by a largely unstressed outer skin:

Representation of original XJ13 monocoque/chassis.

In essence, the final design for the monocoque/chassis consisted of three main elements:

The design of the front suspension went through a few different incarnations as the car was being assembled. Derrick White, Jaguar's talented Race-car Engineer argued for a cutting-edge design (for the time) using widely-spaced upper and lower wishbones. This would have given better handling and a greater possibility of maximising the benefit of the wider tyre widths which were increasingly being used in the mid-1960s. His persistent arguments were repeatedly blocked by Bill Heynes who favoured a more tried-and tested production-based suspension. Heynes eventually prevailed and a design, based on the 1964 Lightweight E-Type was adopted - albeit with coil-over shocks in place of torsion bars.

This decision was one of the things that led to Derrick White becoming increasingly frustrated and his eventual defection to Cooper - a great loss to Jaguar. White went on to design the GP-winning Cooper-Maserati of 1966. Heynes, at the time, had been given direct supervision of the XJ13 project and it has been argued that his enormous workload at the time contributed to the slow development of the XJ13. Fortunately, Mike Kimberley was eventually given day-to-day responsibility for the car and development then continued at a greater pace.

Meanwhile, in 1964 when the car had reached an advanced design stage - on paper at least - Jaguar conducted an investigation into the best materials of construction for the chassis/monocoque. They considered mild-steel, aluminium and titanium. The investigation concluded:

In the end, the chassis sections coloured yellow/green in the drawing above were fabricated from mild-steel. The main centre section was fabricated from aluminium.

According to Peter Wilson, who actually lent a hand in constructing the XJ13:

The modern equivalent, Aluminium 5251 (NS4), is available and will be used for the recreation along with steel pressings where appropriate. I must admit to some relief that Jaguar didn't choose titanium

For those engineers amongst you, and those well-versed in the mysteries of things such as Young's Modulus (I certainly don't include myself here!), the following summarises some of the data presented in Jaguar's investigation into material choice:

As is well-known, there is no such thing as a chassis that doesn't flex, but some are much stiffer than others. The choice of material is critical in this respect. The range of chassis stiffness has varied greatly over the years from about 500 lbft/degree in the 1930s to more than 20,000 lbft/deg in a modern race car. I should be able to measure the stiffness of my completed chassis and it will be interesting to compare the all-steel "trial" chassis to the final version.

Different chassis designs each have their own strengths and weaknesses. Every chassis is a compromise between weight, component size, complexity, vehicle intent, and ultimate cost. And even within a basic design method, strength and stiffness can vary significantly, depending on the details. There can be no such thing as the "ultimate chassis" for every car, because each car presents a different set of problems. The XJ13 chassis gave a whole new challenge because of the intention to mount the engine as a fully-stressed member - with the whole of the rear suspension hanging off the engine/transaxle. I believe this would have beaten Colin Chapman's Lotus by a few years had the XJ13 actually raced. Jaguar carried out a number of theoretical investigations into how well the car should stand up to the torsional loads applied to the chassis because of this arrangement and the final rear chassis design took these anticipated loads into account. The front suspension arrangement bears many similarities to the E-Types with steel tubing attached to the front bulkhead and Jaguar will have built up much experience of this design.

It may seem that an aluminium chassis was always the logical choice, but this is not necessarily true. Aluminium is more flexible than steel or titanium. Indeed, the ratio of stiffness to weight is almost identical to steel, so an aluminum chassis must weigh the same as a steel or titanium one to achieve the same stiffness. Aluminium has an advantage only where there are very thin sections where buckling is possible. This certainly applies to the large sill and floor sections.

In the end, the "unintended crash test" crash at MIRA in 1971 demonstrated better than anything else the soundness of Jaguar's basic chassis design. Although there was considerable damage to the outer structure, the basic chassis/monocoque survived almost intact. More importantly, the legendary Test Driver, Norman Dewis, survived unscathed.

A question often asked of me is,

"How many prototype V12 quad-cam engines were built by Jaguar and where are they now?"

As I reported on this blog back in May 2010, the answer is SIX. Of this six, only three progressed beyond test-bed stage and were installed in cars. A seventh engine was assembled as a 60° V8 and run on Jaguar's test bed. The V12 block for this engine was converted into a V8 using a special crankshaft with throws for only eight of the twelve cylinders. There were plans to assemble an eighth engine but it never reached the test bed stage.

The above has now been confirmed by XJ13-expert Peter Wilson in an excerpt from his forthcoming book which appears in the November 2011 issue of "Jaguar World". I can now add further confirmation of these facts from a collection of previously unknown and unpublished original documentation. These documents were in the personal collection of the late Claude Baily - the architect of Jaguar's quad-cam V12, their legendary XK engine and quad-cam 90° 8 litre V8 amongst others.

Jaguar's Claude Baily.

Claude Baily joined the SS Jaguar drawing office during the second World War and his engineering talents were soon exploited by Jaguar. Baily became intimately involved in Jaguar's plans to replace their pre-war engine designs with a new generation of engines designed to power their latest saloons. He is perhaps best known for his part in the design of the legendary XK twin-cam engine.

Claud Baily's appointment letter.
© Copyright Tony Bailey (WPO Communications) - not to be reproduced without permission.

Spending long war-time nights fire-watching in a small office above the assembly tracks in Coventry, in the company of William Lyons, William Heynes and Walter Hassan, the architecture of the world-beating XK engine was laid down. The new engine was required to reliably provide a minimum of 160bhp, have a long service life and be refined in operation. Before the end of the war, a number of experimental single-cylinder and full engines were evaluated. The following original document from 1941 is likely to relate to one such experimental engine. J.A.Prestwich was better known by its initials "J.A.P." whose engines were used in many famous motorcycle marques and early aeroplanes. Customers included Morgan, Triumph, Brough Superior, AJS and HRD.

12th December 1941 - letter to SS Cars referring to experimental engine.
© Copyright image - not to be reproduced without permission.

4, 6, 8 and 12 cylinder configurations were all considered at this very early stage but it was the 4 and 6 cylinder versions that were finally adopted. It has to be said that the BMW 328 engine played an important part in formulating the architecture of these engines. Indeed, Heynes was great friends with an owner of a 328, Leslie Johnson, who loaned his 328 to SS Cars for evaluation.  Johnson was a British racing driver who competed in rallies, hill climbs, sports car races and Grand Prix races. Johnson's car was highly developed and had raced pre-war. In my opinion, the styling of the XK120 owes much to the BMW. A BMW saloon was also acquired by SS during the war and was fitted with one of the early experimental engines (the "XG"). Walter Hassan used this car as his own personal transport for an extended period for evaluation. One of Jaguar's own 2.5 litre SS Saloons was also used for testing the prototype engines although most of the development work was carried out on the test bed.

3.5 litre experimental XK engine - drawing produced to calculate compression ration.
© Copyright image - not to be reproduced without permission.

Left to right - Walter Hassan, William Heynes, Claude Baily.
© Copyright image - not to be reproduced without permission.

Heynes and Baily applied all their thoughts on engine design to the XK engine although they later commissioned Henry "Harry" Weslake to help optimise their design. Jaguar already had a long association with Weslake, a cylinder head specialist who had been instrumental in modifying the side valve standard engine used in the first SS sports car. He also worked on the larger SS engine. It is believed he was involved in the design of every Jaguar engine up to and including the V12 of the early 1970s.

Harry Weslake - © Copyright image - not to be reproduced without permission.

The following Weslake report gives a fascinating insight into his evaluation methods and his closing summary bears testament to the soundness of the XK basic design. Weslake concludes:

".... The engine has stood up remarkably well through these series of tests. The valve gear has remained quiet throughout, there has been no sign of variation in oil pressure and the engine improves in power out-put the longer it runs. The tests have been very severe, particularly the distribution ones, but never once was any mechanical trouble experienced. It is suggested that some breather attachment should be developed in order to keep a small depression in the crankcase so that oil corrosion can be minimised and this would also help to stop oil leaks, particularly in the valve chest covers ..."

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

The camshaft drive was by duplex roller chain - an arrangement that was carried forward to the quad-cam V12 prototype engines. This arrangement was used in the first engine installed in the XJ13 as well as the second engine built and tested in a Mk.10 Jaguar. The "genetics" of the XK engine could clearly be seen in the later quad-cam V12. The following page of sketches (made by Claude Baily around 1949/50) clearly show how he was formulating a suitable cam drive for a quad-cam engine. It is believed the sketches were produced as a precursor to designing and building a quad-cam 8-litre 90° V8 engine for a post-war military application. A similar architecture found its way into Baily's quad-cam V12.

Baily's drawings showing his ideas for a quad-cam duplex chain drive
© Copyright image - not to be reproduced without permission.

Claude Baily had been working on a quad-cam 60° since 1949/50 - perhaps earlier. By the February of 1951 a fully-working engine may have been running on the test bed. This 12-cylinder engine was later developed as an 8-cylinder variant for military use. The following quad-cam V12 performance data was recorded on the 19th February 1951.

Claud Baily's 1950/51 60° quad-cam 8-litre V12 engine performance data.
© Copyright image - not to be reproduced without permission.

The following picture shows Baily's data in his own hand. Was this an estimate/conjecture or are they figures actually recorded on the test bed?

Claud Baily's 1950/51 notes.
© Copyright image - not to be reproduced without permission.

In 1962, Baily was given the go-ahead to develop his design as a 5 litre V12 to challenge at Le Mans. Although primarily designed for racing, consideration was also given to using the engine in production cars. At least two years before the go-ahead, Baily's 60° V12 engine was being proposed as a future Jaguar engine with a range of possible capacities as the following memo from Claude Baily to William Heynes demonstrates:

5th December 1960 memo - "POSSIBLE FUTURE RANGE".
© Copyright image - not to be reproduced without permission.

The quad-cam V12 engine project was given the code "XJ6" - not to be confused with the saloon of the same name. "XJ6" followed on from "XJ5" which was the code name given to the Mk10 replacement (eventually to become the 420G). Two Mk.10 cars (XJ5/4 and XJ5/5) were to become mules for the production variant of the "XJ6" racing engine. The following memo confirms that six prototype engines were being developed.

25th November 1964 memo - "12 CYLINDER ENGINES".
© Copyright image - not to be reproduced without permission.

The first two engines (XJ6/1 & XJ6/2) were first assembled to almost identical specifications which included dry-sump lubrication and Lucas mechanical fuel injection. In April 1966 XJ6/1 was installed in the XJ13. The second engine, XJ6/2, was installed in a Mk10 Jaguar (XJ5/5 - manual gearbox) on 14th April 1965. It was converted to wet-sump lubrication although its Lucas fuel injection system remained. After six months of testing in the Mk.10, XJ6/2 was removed from the car and reunited with a dry sump for further test bed development. In March 1966 it's dry sump was again converted to enable fitment in a second Mk.10 (XJ5/4 - automatic gearbox). By this time it had acquired a sextet of SU carburettors. It ran for almost 35,000 miles in this car before it was removed and replaced in XJ5/5. It was finally removed from the latter car and placed on the test bed for further development/testing until it was put into store in March of 1969. It remained as a complete engine until I acquired it in 2010. It is now being rebuilt to its original specification and will be placed in my replica of the 1966 XJ13.

So, to answer the question "How many quad-cam V12s were built and where are they now?" SIX quad-cam V12 engines were built.

XJ6/1 The first quad-cam V12 built but only the second to leave the test-bed and be installed in a car (XJ4/1).  Damaged in 1967 and retained as a spare by Jaguar. 

XJ6/2 The second quad-cam V12 built and the first to be installed in a car (XJ5/5) Survived as a complete engine and sold by Jaguar in the mid 1970s. Currently under restoration to original specification (same build spec as XJ6/1).

XJ6/3 Only ever ran on the test bed in a variety of configurations. Has not survived.

XJ6/4 Built using cast iron block and ran on test bed. Has not survived.

XJ6/5 Internally modified to run as a V8. Ran on test bed for a short while in 1965. Surviving components are with a collector in the US.

XJ6/6 No records exist. It is believed this engine was never actually assembled.

XJ6/7 Built to trial a die-cast "open-deck" engine block.  Installed in XJ4/1 (XJ13) to replace its original engine when damaged in 1967. Remains in the car to this day.

XJ6/8 Built to competition spec with ultimate development of cylinder heads but never left the test bed. Cannibalised whilst in storage in 1969. Cylinder heads placed on XJ6/2 which remain with it until today. The engine block found its way into an XJ13 replica built by Bryam Wingfield for the collector Walter Hill. 

It is interesting to note that Jaguar's XJ13 currently has a die-cast block that differs from its original XJ6/1. This die-casting process is used to reduce costs and will have been more relevant for a production as opposed to competition engine. The following letter indicates the target casting weight of a V12 block (OXW 5620 is an experimental part number current at the time of quad-cam testing)

Die Casting Quote.
© Copyright image - not to be reproduced without permission.

The XJ13's rather poor power to weight ratio when compared with its likely Le Mans competitors may have contributed to this attempt to lighten its weight?

As Mike Kimberley recorded after a test of the XJ13 at Silverstone in 1967:

BHP per lb weight

Ferrari P4/ .210

Lola Chev/ .207

Ford Mk4/ .206

XJ13/ .177

It is also interesting to note that the engine currently installed in the XJ13 has a single OPUS 12 cylinder distributor. Its original engine, XJ6/1, as well as XJ6/2 were fitted with twin 6-cylinder distributors.

XJ6/2 Original twin distributors as originally fitted to XJ6/1.
© Neville Swales.

XJ13 single 12-cylinder distributor on XJ6/7 engine.
© Neville Swales.

The rebuilt XJ6/2 will, of course, be built using its original twin distributors. In 1966 Claude Baily was charged with pricing the OPUS system. The following letters give an interesting insight - comparing the various options under consideration.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

© Copyright image - not to be reproduced without permission.

There are other differences between the XJ13's original engine (XJ6/1) and the one currently installed in the car (XJ6/7). One is the inlet manifold throttle bodies. The first photo shows the original (1967) arrangement with dual throttle bodies (and separate mounting plates - coloured yellow) and the second shows the current arrangement (photo taken 1973) with individual throttle bodies and a single mounting plate on each head. Note also the different cam cover treatment - the earlier engine has the "trademark" polished cam covers wheras the currently-installed engine has a crackle-black finish.

1967 (original car)
© Copyright image - not to be reproduced without permission.

1973 (rebuilt car)
© Copyright image - not to be reproduced without permission.

Background

Work has finally commenced on building up the chassis/monocoque of my recreation of the 1966 Jaguar XJ13 - a "snapshot" of the car as it was in 1966 before it was crashed and modified. Almost 18 months of painstaking and exhaustive research has revealed details of the original 1966 car which will hopefully allow us to recreate the car as Malcolm Sayer intended - without the later "1970's" modifications/enhancements.

Research is still ongoing and takes advantage of recent, previously-unpublished, documentary finds as well as details soon to be revealed in Peter Wilson's forthcoming book - the definitive story of the XJ13 and the quad-cam engine that powered it. Peter's book is scheduled for launch towards the end of November 2011. A tantalising glimpse is available on Paul Skilleter's website.

Peter Wilson book - "XJ13".

Piecing together details of the original car has been an exhaustive and a very time-consuming process. Originally centred around the relatively few original documents that have survived as part of Jaguar Heritage's archive, research was supplemented by face-to-face and written communication with surviving ex-Jaguar employees. Chief amongst these is Peter Wilson (Jaguar Competition Department 1961 - 1966). Since leaving Jaguar, he has worked in a number of prominent and senior positions in the automotive industry including time spent Brico Engineering, Cummins Diesel Engines and British Leyland. Since his retirement in 1999 he has written the definitive work on the Competitions Department between 1961 and 1966 including not only the XJ13, but a significant era in the racing and development of the E-Type. I can heartily recommend Peter's book "Cat Out of the Bag" which is available from Paul Skilleter books at www.paulskilleterbooks.co.uk. Others have included the Jaguar automotive electrician Bryan Martin who actually wired up the original car and applied all those "temporary" red dynatape stickers (which still "grace" the car almost 50 years later ...).

Another invaluable resource has been Norman Dewis himself - not only from his numerous recorded interviews and recollections but face-to-face discussions at Jaguar Heritage. I am the proud owner of a personally signed copy of Norman's autobiography "Norman Dewis - Developing the Legend" which contains some facts about the XJ13 - the whole book is a fascinating read.

Norman Dewis' Autobiography - "Developing the Legend".

The work of creating the car has been entrusted to North Devon Metalcraft - a long-established family-run company manufacturing high quality, complete steel and aluminium motor bodies and replacement panels. ND Metalcraft was founded over thirty years ago by the father of John and Paul Evans who run the company today. Their late father was a time-served craftsman with experience stretching back to the 1950's. As well as being a Freeman of the City of Coventry he handbuilt the first London Black Cab. He passed his skills on to his sons Paul and John and now ND Metalcraft are best known for their body/chassis work on the Shelby Cobra, Jaguar, Aston and Triumph TR. The quality of their work is beyond reproach and I am confident in their ability to deliver an absolutely authentic 1966 XJ13 copy.

North Devon Metalcraft.

North Devon Metalcraft - XJ13 monocoque buck in the company of an Aston and Triumph.

As I researched the original XJ13 it very soon became apparent that there is no such thing as an original XJ13 blueprint, construction plans or drawings. To make matters worse, Jaguar have never allowed anyone close enough to the XJ13 to take detailed measurements for the purposes of manufacturing a replica. Replica manufacturers who claim they have had privileged access to the XJ13 are not being truthful. Others who say they have copies of original manufacturing plans are telling lies. Testament to this are the number of inaccurate XJ13 replicas currently in existence - to be truthful, I have yet to see a replica that accurately replicates the current car - and I have seen lots in the last 18 months!

The detailed information needed to reconstruct the original 1966 XJ13 has had to be pieced together from original drawing fragments, original Malcolm Sayer 3D measurement data, period photographs and the surviving remains of the original car.

Very early photo of the 1966 XJ13 clearly showing original lines of front and rear wheelarches.

It has to be remembered that the car currently in the Jaguar Heritage Collection differs in many respects from the 1966 original. Although many components such as the engine, instruments, chassis/monocoque, bonnet lid etc survived the crash intact, it is unlikely that original components such as the windscreen would actually fit the rebuilt car's body and there are numerous differences in the body form - some subtle and others rather more substantial (such as later 1970's flared wheelarches and the overall length of the car).

Crashed XJ13.

However Jaguar's XJ13 does provide clues to be able to "peel back" changes made in 1972/73 and reveal many features of the original car. For example, evidence of where the crumpled remains of the original body was cut away from the monocoque and how the new body/outer-sills were attached can be seen in the following sequence of pictures:

The following original 1965/66 photograph (reproduced with permission) shows the original sill in place in the car. The TIG weld and breather(?) holes are highlighted in yellow.

Photo of original 1965/66 monocoque. (The more eagle-eyed of you may notice the dash panel instrument layout differs to that in the current rebuilt car as well as their E-Type origins).

A separate panel is riveted to the floorplan (highlighted below) and meets the folded-over sill along the TIG weld. I suspect this panel had to be separate because a row of rivets attaching it to the floorplan can clearly be seen when the car is viewed from underneath (it would not have been possible to place these rivets if the sill/floor was formed from a single sheet of aluminium and folded back over itself to meet the floor).

Photo of original 1965/66 monocoque.

The car suffered substantial damage to its sills during its crash in 1971. Indeed, Norman Dewis' account of the crash suggests a sill may have made contact with a sand-filled oil drum. The following photo of the rebuilt car gives evidence that the outer sill was replaced and joined to the upper sill cover at its outer edge. The join was masked by the door rubber sealing trim and was roughly pop-rivetted into place.

Sill detail - rebuilt car.

Use of 3D Reverse-Engineering

A major contributor to the project has, and continues to be, Stuart Brown of 3D Engineers. Without these cutting-edge reverse-engineering techniques, the ability to produce an absolutely authentic and accurate replica would have been severely compromised.

Stuart Brown scanning original quad-cam V12 engine.

What is 3D Engineering?

In simple terms, 3D scanning is a fast and supremely accurate method of putting physical measurements of an object onto the computer in an organised manner, resulting in what is commonly called 3D scan data. Typically, the 3D scan data is represented with a scale digital model or a 3D graphical rendering. Once the scan data is on the computer, all of the dimensions of the physical object can be taken, such as length, width, height, volume, feature size, feature location, surface area, etc. This even extends to being able to calculate things such as centre-of-gravity, suspension clearances, how well various components such as radiators etc will fit in the final car etc.

Components that are known to have been used in the original XJ13 can be scanned in this way and added to the 3D scan data. This includes things such as the windscreen (made using original tooling), E-Type rear light clusters and front suspension components.

In general, a device that captures 3D information from a physical object is referred to as a 3D scanner. There are many different methods for capturing the 3D measurements of a physical part and thus, many different types of scanners. Stuart himself makes use of various scanners including an OptiNum 3D optical scanner.

Stuart Brown of 3D Engineers trying his hand at wheeling an aluminium panel under the watchful eye of John Evans of ND Metalcraft. The verdict was that "Stuart should stick to what he is best at - 3D Engineering ...

Because the 1966 XJ13 doesn't exist in its original form it has been necessary to supplement the digital scan data with data from other sources. Even if Jaguar made the rebuilt XJ13 available to us for scanning (unlikely in the extreme!)it would be of little value to us because it differs from the original 1966 car. One of the major sources of this 3D data for the 1966 XJ13 are documents containing measurements made in 3D space originally by Jaguar - possibly Malcolm Sayer himself. As Peter Wilson describes in his book "Cat Out of the Bag", Bob Blake built the original XJ13 by starting with a baseboard marked out with 10" squares. Malcolm Sayer's design was translated into 3D measurements by recording various points in 3D space relative to the baseboard markings. For example, the left-hand steering rack inner ball joint was defined as being 24.330" from the zero line on the baseboard, 17.320" perpendicularly up from this and 14.740" from the baseboad centreline.

Location of left-hand steering rack inner ball joint in 3D space.

I have obtained a large number of original key measurements such as this which precisely identify the location of key components such as front and rear suspension, monocoque/chassis dimensions etc. All of these critical measurements have been incorporated into Stuart's digital representation of the car.

The first task is to recreate the 1966 monocoque chassis - as was the case when Bob Blake picked up his first piece of aluminium and pondered Malcolm Sayer's measurements in 1965. The following picture shows the original XJ13 monocoque in the process of construction in 1965/66. If you look very closely at the bottom right of the picture it is possible to make out the 10" x 10" squares drawn on the baseboard.

Original 1966 XJ13 - chassis/monocoque construction detail - reproduced with permission.

This second picture is a representation of what the finished monocoque/chassis will look like.

Representation of original XJ13 monocoque/chassis.

We decided to produce two major buck/formers for our recreation - one for the chassis/monocoque and a second for the body itself. The following pictures show a digital representation of the chassis/monocoque buck followed by its full-size version. The central section and bulkheads are removable and will be replaced by the body buck when the chassis/monocoque is complete and we are ready to start work on the body. The plan is to first build a basic monocoque using sheet steel before committing ourselves to a full monocoque built using original-specification aluminium. I plan building a total of two full aluminium monocoques.

According to Peter Wilson,

The modern equivalent, Aluminium 5251 (NS4), is available and will be used for the recreation along with steel pressings where appropriate. This attention to detail will extend to the choice of aviation-quality rivets as original (I have seen too many oversize rivets used in replicas!)

Chassis/Monocoque - digital image.

Chassis/Monocoque buck.

The XJ13 used E-Type front suspension using coil-over shocks in place of torsion bars, vented discs and specially-manufactured calipers. All of these components will be used with modifications as per original.

Paul (ND Metalcraft) identifying data points on bulkhead from original Jaguar XJ13 data.

The front of the sills/floor. A "trial monocoque" being constructed using sheet steel. Once we are happy with the details we shall work using the rather more expensive original-spec sheet aluminium. I shall end up with a complete surplus steel monocoque before we begin building the final aluminium version. I don't know what I shall do with it yet - any offers/suggestions?

Rear view. The cross-hatched section will be removed. Note the width of the sills - seems I will have to lose some weight to fit in! The original cockpit is rather cramped (as is the cockpit of the rebuilt car).

"Trial" Chassis/Monocoque - side view.

To be continued ...

In January of 2011, on a very cold January morning, the restoration of my quad-cam V12 began in earnest with a total stripdown and detailed examination. The task of rebuilding this important engine has been entrusted to David Butcher.

David can draw on his vast experience gained from many years of rebuilding Jaguar engines from the 1960s to date. He has had a long involvement with Jaguar engines since his days working alongside the late Ron Beaty at Forward Engineering. Although in "semi-retirement", David's skills are very much in demand today - particularly by racers and enthusiasts. David has worked on all variants of Jaguar's classic engines including the Group C and prototype Le Mans racers.

David Butcher starting work on the prototype V12.

We were privileged to be joined at the initial engine stripdown by Peter Wilson and Jim Eastick. Both Peter and Jim worked at Jaguar on projects associated with the XJ13 - Peter on the car itself and Jim on the prototype's V12 engines.

From left to right - Peter Wilson, David Butcher and Jim Eastick.

I was fascinated to learn from Jim Eastick that my engine has a direct connection with the legendary Ron Beaty as it was Ron who actually ran and optimised my engine on the Jaguar test bed. Beaty joined Jaguar and made his way up to being one of the all time greats at the works. He worked in the former competition dept and was experimental engineer for the V12. In the late 1960's Ron Beaty formed the company Forward Engineering which made him a household name in the Jaguar world, creating power units for British and world water speed records, Lister Jaguars (Beaty created the original Lister XJS with Brian Lister) as well as many track records both here and abroad. The original TWR XJS's were also "Forward " powered as were many small volume constructors like Panther. David Butcher worked alongside Ron Beaty at Forward Engineering and played an important role in some of Forward Engineering's various projects. Other notable "Forward Engineering Graduates" were Rob Beere and Carl Taylor of Rob Beere Racing.

While David worked on the engine, I was treated to an accompanying dialogue of recollections of life at Jaguar at the time of the project between Peter, David and Jim - memories sparked by details of the engine revealed as the stripdown progressed - recollections not only of the engine itself but also the many individuals involved at the time. Sadly many of these individuals are no longer with us. Jim also brought with him his personal notebook containing notes made while the prototype engines were actually being run on Jaguar's Test Beds - a book he kept very close to his chest!

Jim Eastick consulting notes made during prototype engine testing.

My engine was the second engine assembled and is believed to be one of only three engines surviving having left Jaguar as a complete engine. Two of the three engines remain with the XJ13. There is a fourth engine which was assembled from a collection of new and used parts left over at the end of the project and installed in a replica for the late collector Walter Hill by Bryan Wingfield. As the stripdown progressed it soon became clear that the engine was not only complete internally but was in quite remarkable condition despite its 40+ years of storage.

Head removal.

Jaguar's habit of liberally applying "Wellseal" to gasket surfaces was very much in evidence! Having removed the heads, the condition of the bores and pistons became apparent. Although there is slight surface oxidation on the crowns of the cast alloy pistons, this is to be expected on an engine that has been stored for this period of time. It does confirm that the engine has spent its last 40 years undercover and in dry conditions. The slight oxide buildup was only present on the pent-roof piston crowns and the remainder of the pistons was found to be in quite remarkably good and usable condition. The lack of any significant carbon buildup does tie up with the original testing logs which indicate the engine was only run for a short time on Jaguar's test bed before being removed for storage in December of 1969. The final bout of testing was for emmision comparisons with the SOHC production engine.

The cylinder block is a L.M.8 sand casting and has a sump face on the crankshaft centre line. This is in contrast with the later SOHC V12 which had a much longer "skirt" which helped increase block stiffness. The prototype engine is a solid casting as opposed to the die-cast "open deck" design of the later engine. This makes it a rather heavy engine which is difficult to manouevre by hand - ask me how I know!

Cylinder heads showing "tin" gaskets. In the foreground can be seen the original twin distributors. Twin distributors were used in the original 1966 XJ13 and were only replaced with a single "modern" V12 distributor during the car's rebuild in 1972/73.

Hemispherical combustion chambers.

The V12 cylinder head design is very similar to the 6-cylinder XK engine in basics such as valve operation with a few significant differences. In an attempt to arrive at a more compact and efficient combustion chamber, the chamber depth was reduced to 1.03" (from the XK's 1.30") and the included valve angle was reduced.

As explained by Jim Eastick, the V12 prototype engine has equal firing impulses along each bank and can be carburetted as an in-line 6 cylinder. The bore and stroke is 87mm x 70mm giving a displacement of 4991cc.

All prototype engines were fitted with twin 6-cylinder distributors. One of the many changes made when Jaguar rebuilt the XJ13 after its crash in 1971 was their replacement by a single 12-cylinder distributor. One of the two distributors, the "master", contained two sets of contact-breakers plus a centrifugal advance mechanism that served both distributors. The second distributor, the "slave", was simply a distributor for the H.T. current. My engine will be rebuilt with both distributors as original.

Jim Eastick explaining how he had added extra springs to the "master" distributor in an attempt to reduce points bounce during testing.

The heads on my engine are numbered 18 and 19. This confirms them as the ultimate development of the prototype cylinder head having an optimum subtended angle of 41 degrees to the valve axis with camshaft centres raised by 0.25". The cylinder heads remaining with the XJ13 may have never achieved the widely-reported maximum power of 502 bhp at 7,600 rpm achieved by an engine with this design of head.

The following picture shows the modified sump fitted to my engine. Although it is the engine's original racing dry sump, it was considerably modified in period to enable its fitment in the two Mk10 Jaguar "mules" for testing. The original gear scavenge/pressure in-sump gear pump was found to be in place but modified so that drive was transferred to a rear "wet-sump" pickup. The welded-up position of the original scavenge/pressure outlets can be seen at the front of the sump. The plan is to return the original sump to dry-sump specification.

Modified dry sump.

The four studs on the skirt of the block are used to not only mount the engine but also to provide a location for the rear trailing arms. There will be a corresponding pair of locating studs on the final sump. The engine/transaxle in the XJ13 supports the entire rear suspension.

Seen here is part of the duplex chain cam-drive arrangement - incidentally, as originally fitted to the XJ13 engines and not gear-drive as widely thought.

Chain-drive to cams.

The next few pictures show the sump being removed - revealing components not seen since the engine was assembled in Coventry in the late 1960s.

Preparing to remove the sump under the watchful eye of Jim Eastick.

Sump removed revealing combined scavenge/pressure pump and shaft used to transfer drive to the rear oil pickup. As with the later SOHC engines, a steel plate extends the full length of the crank.

Oil pump detail.

Chain drive to oil pump.

The engine has seven 3" diameter main bearings which means the later shells can be used (perhaps with slight modification to oil-holes). The big ends are unique which may cause some problems in finding replacements. When Jaguar recently rebuilt the XJ13's engine they found it necessary to increase the diameter of the conrod big ends to accept "off-the-shelf" bearing shells. This avoided a cost of something in excess of £20,000 to tool up for the prototype's unique bearing size. However, we have yet to fully explore whether or not the original size shells can be found. The crank pins are 2.187" diameter and are 1.20" wide to accept the side-by-side conrods. The conrods are offset 0.75" bank-to-bank. The crankshaft is made from forged steel and is lubricated using an end-to-end feed from grooves in the main bearings. The same sludge trap system as used on the earlier 6-cylinder XK engine was used with transverse oil feed holes. Although we have yet to confirm whether or not the crank was nitrided it is known that Jaguar used a EN 40 nitrided crankshaft in the competition V12.

David then began to remove the timing-chain cover so that pistons and crank could be removed.

Preparing to remove timing cover.

Timing cover removed.

The following picture shows detail of the lower two chains (four separate chains in total). One chain drives the oil pump while a second takes drive to intermediate sprockets - one for each head. Another sprocket is used to drive the twin distributors and Lucas fuel injection metering unit via a "Jackshaft". A hydraulic chain tensioner can be seen towards the bottom of the picture. The two top chains (driving the cams) are tensioned by an external nut applying pressure to a slipper.

The complexity of this chain layout was a factor in deciding to go with a SOHC layout for the production engine. The weight and cost could be reduced using a single chain drive with four sprockets compared to the prototype's four chains and twelve sprockets. Also, the noise level of the quad-cam layout was unacceptably high for a production engine. However, for racing purposes the quad-cam layout was preferred.

Timing chain detail.

Drive removed from oil pump.

Steel cover plate and scavenge/pressure pump removed.

Referring to original notes .....

Oil pump.

Removing slave distributor drive.

Distributor drive "jackshaft"

Piston sees light of day after 40 years.

All bearing shells were in remarkably good condition - confirming the engine's short time on Jaguar's test bed before the engine was removed for storage.

Journals also in good condition.

"Yours Truly" lends a hand.

Connecting rod still polished and shiny after all these years.

Preparing to remove crankshaft.

Jim Eastick remembering modifications to oiling system.

Detail showing "grooves" around oil holes on alternate big ends.

Slip-fit dry liners.

Crankshaft removed. Bearing shells were all in excellent condition.

Now that the engine has been stripped it can be given a detailed examination/measurement in readiness for its rebuild. As a matter of course things such as valve springs and (probably) valves will be replaced. After standing for more than 40 years it makes sense to replace items such as this - the thought of a detached valve in the rebuilt engine doesn't bear thinking about! Fortunately, we are well-blessed in the UK with skills and expertise to be able to build an engine such as this.

To be continued ...

As my quest to recreate an exact copy of the 1966 XJ13 continues, I came across the story of the man largely responsible for making the original body - Bob Blake. What follows is the story of a man able to translate the designs of people, such as the legendary Malcolm Sayer, into metal. Contemporaries of Bob Blake described him as "An Artist in Metal".

The late Bob Blake - 1916 to 2003.

Blake was born in 1916 at the Fort Totten Sioux/Dakota Indian Reservation, Elbow Woods, North Dakota, USA. The original Reservation at Fort Totten was located near Devils Lake. After 1905 almost half the land was sold to the Government and opened up for white settlement.

Fort Totten Indian Reservation.

The young Bob Blake took up panel beating as a hobby and was entirely self-taught. He taught himself to weld at the age of 19 and a lifelong interest in racing cars and their construction began.

After entering the services he visited the UK in 1942 with the US Third Army where he met his future wife, Jean. At the end of the war he returned to the US and set up a workshop building sprint and race cars - including midget racers. He didn't only make bodies, he also lent his hand to making parts such as chassis, fuel tanks, radiators, steering and almost everything else. As his skill and reputation grew, he progressed to work on Indianapolis cars for racers such as Ted Horn and Tommy Hinershitz. One of his early commissions was to manufacture parts for Alec Ullman's Alfa Romeo - Ullman, a Russian-born MIT graduate went on to found the Sebring 12-hour race in 1950 in an attempt to rejuvenate sports car racing in the US.

Bob Blake remained in touch with Ullman and received a phone call from him in 1950 during a visit to the UK. Ullman told him that Briggs Cunningham had entered two Series 61 Cadillac Coupe deVilles at Le Mans - one with a standard body and the second with a streamlined body. Howard Weinman, an aeronautical engineer, was tasked with streamlining the Cadillac. Weinman began by testing designs in wind tunnels. The resulting design was wide, had a low center of gravity, aerodynamic, and lightweight due to an aluminum body. Many people agreed that the appearance was not favorable and it received the name 'Le Monstre' by the French press. During preparations for the event, the standard car had been driven into the back of 'Le Monstre' and both needed urgent repair.

1950 Cadillac 'Le Monstre'.

Bob Blake immediately flew out to Le Mans and worked non-stop without sleep for 48 hours to repair the cars. He succeeded with only minutes to spare before scrutineering.

In the race, Cunningham and Phil Walters were the drivers of the 'Le Monstre'. The coupe was driven by Miles and Sam Collier. The traditional sprint start, where the drivers sprinted to their vehicles, revealed the doors were locked. The problem was able to be solved by reaching in through the window and unlocking the door - not a good way to start a race! On the second lap, 'Le Monstre' lost control and ended up in a sandbank where it sat for twenty minutes before Cunningham could dig it out. 'Le Monstre' was now four laps behind. The Coupe had a bit of misfortune as well. Part way through the race, it had to come to a complete stop while a stray dog made its way across the track. Later on in the race, it barely made it back to the pits due to low fuel. When the checkered flag fell, both cars were in impressive standing. 'Le Monstre' had battled its way back from 35th place to finish in 11th. The coupe was in 10th after averaging 81.5 mph per lap. To finish the race was a major accomplishment, a testament to both driver and car. Their accomplishment was even more significant since the Coupe had lost its first and second gears during the race.

Cunningham's ambition was to win at Le Mans with an American car and, to this end, set up a company in 1950 with Alfred Momo. Bob Blake's efforts at Le Mans had clearly impressed Cunningham and he employed Blake in his new company - giving Blake overall responsibility for building his Le Mans contenders. Bob Blake built every Cunningham car until the closure of the company in 1955. Although Briggs Cunningham never realised his ambition, he did come a creditable fourth in his Blake-built C-4R in 1952 and finished a respectable third in 1953 behind the winning Hamilton/Rolt Jaguar C-Type.

The Bob Blake-built C-4R on its way to fourth place at Le Mans in 1952.

Briggs Cunningham held Bob Blake in high regard and, when he closed his company in 1955, he wrote a glowing reference for the jobless Blake:

" ... He designed and built all our competition cars that raced at Le Mans from 1951 thru 1955, doing most of the work himself. He is one of the best aluminium welders and formers in the USA, and we found him invaluable in our racing department. Bob is a most efficient worker, and a real artist in sheet metal work of all kinds."

"His character is excellent, and his interest in his job profound. He loves racing cars of any kind, and is a wonderful man to have in the team at races, as he can make all manner of alterations and repairs very quickly, when the need arises. Bob was one of our most valuable team members, and I would highly recommend him to any firm or individual looking for one of the best body men in the world today. His loyalty is outstanding, and I frankly hate to lose him."

Bob Blake (far right) at Cunningham's company.

Bob Blake had come into contact with people such as Lofty England and other racing team members whilst racing with Cunningham and so was already known to them. In November of 1955 Blake joined Jaguar and began an association that continued for more than twenty years.

One of Blake's first responsibilities was to convert the stock of obsolete D-Type racers into road cars - the XKSS cars. He altered the D-Type body and added parts such as bumpers and hood frame. In his own words, Bob Blake said,

" ... I made all the frames and bits and pieces, including all the wooden tools to make everything from. I made the first set of bumpers by cutting down the big old bumper, using the top radius and the bottom radius, cutting the flute out and welding the two pieces together."

Jaguar XKSS - note the diminuitive bumpers that were to make a return in the E-Type.

Bob Blake was a likeable character who forged relationships with William Lyons and Malcolm Sayer amongst others. Bob worked very closely with Sayer and was able to decipher his mathematical representations of compound curves and produce panels from the data. Malcolm Sayer's way of working was a longhand precursor of the digital CAD techniques used today and he was very much a pioneer in this field. It is pleasing for me to realise that I am using today's equivalent of Malcolm Sayer's calculations in the construction of my XJ13 recreation. Sadly, neither of these two gifted individuals are still around to lend the benefit of their expertise.

After the XKSS, Bob Blake worked closely with Malcolm Sayer in the production of the first E-Type prototype - E1A. Indeed, Bob Blake went on to play a major part in producing the E-Type coupe. Working with an E-Type roadster, he tried different roof treatments within the Competition Department. He said, " ... I had a body in the Comp. Shop ... I took a whole mess of 1/16 steel rods and did a profile, a side elevation of the screen and the roof, flowing into the tail. I'd got all this tacked up and Sir William walked in the door."

"The Old Man looked at it and boy, he liked it. He fell in love with it the minute he walked in the shop. Lyons studied the mock-up for some time in silence, walking around it. He said to me, 'Did you do this, Blake?' I said 'yep'. He responded 'Its good. We'll make it!' "

Jaguar E-Type Coupe.

In 1962 Bob Blake became involved in the car that represented Jaguar's hope to return to racing - the Lightweight E-Type. Peter Wilson, in his book "Cat Out of the Bag" (available from Paul Skilleter Books at /www.paulskilleterbooks.co.uk) reports," .. It was early October (1962) when Bob Blake and Geoff Joyce started work on the first bodyshell. Malcolm Sayer, our aerodynamicist and designer of the D-Type monocoque, had meantime designed an aerodynamic package, consisting mainly of a special coupe top, with the combined objective of reducing both the aerodynamic drag and the frontal area. Malcolm's drawings contained no lines per se, but consisted of a matrix of dimensional points defined in three planes from a common base reference point, which defined the outer surface of the skin panel. His method was unique in the motor industry, but more commonplace in the aircraft design world."

"Malcolm claimed he had been taught this mathematical method of complex surface definition by a German, when they spent a few days together in a tent in the desert, during his time working in Iraq at Baghdad University, soon after the war. It was a system that was relatively easy to use; just a case of marking out the points defined by the co-ordinates on a sheet of plywood, cutting it out, then assembling each piece relative to its datum on to a wooden base and, 'hey presto', you had a complete skin former..."

Malcolm kept his method of mathematically calculating complex surfaces close to his chest ... from Malcolm's drawings, Bob and Geoff, together with Sam Bacon, built a wooden 'egg-box' former for the coupe skin."

Similar documents have survived - defining things such as the windscreen profile, suspension and steering points etc. Data from these are being incorporated into the digital model which will be used to manufacture a similar "egg-box" former for my XJ13 recreation.

Jaguar C-Type "egg-crate" body former.

"Virtual" buck for Bristol engined "special". Body designed by 3D Engineers - the company entrusted with the production of body formers for my 1966 XJ13 recreation.

In 1965 Bob Blake worked on the XJ13 project. His method of working is best described by Peter Wilson, " ... As our surface table was not large enough, or indeed remotely suitable, Bob Blake, Geoff and Roger built a rigid wooden platform on which to build the XJ13 monocoque ... First they constructed a perimeter wooden frame from a 6x4-inch timber, cross-braced at intervals along its length. This was topped with 3/4 inch thick plywood sheet, which they then marked out with '10' lines to enable accurate positioning of each of the myriad of construction reference points defined by Malcolm Sayer's 'drawings' "

" ... the monocoque was constructed almost entirely from NS4 2 percent magnesium and 2 percent manganese, half-hard alloy sheet, mostly of 18 swg thickness (0.048 inches), together with some sheet steel pressings in areas of high and concentrated stress, such as the main engine mountings and front suspension attachment areas."

" ... The floor section and outer sills were formed in two halves and were joined along the centre line of the car with an overlapping, joggled joint and a double row of rivets. The inner sill panels were made up and these, together with the internal half-rounded section inner sill stiffeners, four per side, were assembled to the floor section. At this point the whole job was shipped over to Abbey Panels at Exhall on the outskirts of Coventry for the inner and outer sill joints to be roller welded using their specialised equipment. ... This was then the sole contribution Abbey Panels made to the construction of the original monocoque. With this operation completed and the basic foundation of the monocoque firmly in place, construction proceeded apace with Bob, Geoff and Roger fabricating the majority of the panels and rivetting these in place, while the rest of us helped out with the simpler body items."

Peter Wilson talks of Bob Blake in his book, "Cat Out of the Bag" and Bob's personable character shines though. "... Bob Blake was a totally unique talent. He was a hands-on man, who also had a superb eye for style. Not only could he create a vision of shape and style, but he could then actually make it. He was the 'complete' body man and Jaguar were lucky to have his talents ... Bob was a super bloke, modest, self assured and always helpful. He did not suffer fools lightly and many is the time whilst I attempted some sheet metal work he would appear at my shoulder and say, 'Not like that you silly shit! Here, let me teach you how to do it properly.' And with great patience he would do just that."

Bob Blake in later life.

Rather amusingly, Peter Wilson talks of Bob Blakes "Secret Project". It seems that Bob Blake became rather more industrious than usual and was seen to be squirrelling various car components into the Competition Shop. The secret was eventually revealed to be his personal Ferrari project - a rather mangled 250 GT. The car was soon transformed by Bob into a beautiful blue car - complete with engine rebuilt at home by George Buck! Bob continued his interest in buying and repairing crash-damaged Ferraris and in the 1970s could be seen driving one of his three Ferraris - a 365 Daytona and two GTB 330s.

Described by his other contemporaries as a "delightful gentleman", Bob Blake retired to Northampton in 1978 with his wife and kept his hand in by fabricating small projects such as motorcycle fuel tanks for friends.

This talented key player in the story of Jaguar and the XJ13 passed away on 26th August 2003 at the ripe old age of 87.

Bob Blake's Ferrari Daytona.

On the 3rd June 1965 an internal "Instruction to Proceed (XJ13 Car)" was issued by Jaguar’s Bob Knight – it started, “Build one prototype competiton car …”. Responsibilities for all aspects of the car’s design were allocated – the responsibility for the body being given to Malcolm Sayer, Phil Weaver and Bob Blake.

The body was to be, “Light alloy skin on monocoque structure. Comprising of three main sections”. These three sections were:

• “Body Front Structure” (main skin, front bulkhead, headlamp diaphragms, air-ducts for radiator/brakes etc, internal structure to suit 1964 Jaguar Lightweight E-Type independent front suspension and a boot lid).
• “Body Centre Structure” (floor & sills, fuel & oil tanks, seat back bulkhead, doors and windscreen).
• “Body Rear Structure” (main skin, engine cover, spare wheel, cooling ducts for transmission & brakes, rear lid and rear valance).

Other responsibilities were allocated as appropriate. Rather telling was the comment “For the first car only” which does confirm the prototype XJ13 was planned to be one of many.

By the June of 1965, the quad-cam V12 engine project for the XJ13 was well underway – with the emphasis very much on racing. The first V12 engine to be fitted to any car was my engine (engine number 2) which was fitted to a car codenamed “XJ5/5” – XJ5 being the code name for the Mk10 successor. This engine was fitted to this sable-coloured “test mule” in April 1965 – complete with Lucas Mechanical Fuel Injection and modified dry sump - some two months before the XJ13’s “Instruction to Proceed” was issued. The engine in the “test mule” was built to the same specification as the first engine (number one) which was to be installed in the XJ13 a year later in April 1966.

Overall responsibility for the shape was given to the late Malcolm Sayer – the man already responsible for the Jaguar C-Type, D-Type and later to be responsible for the iconic designs of the E-Type and XJS.

Malcolm Sayer, 1916-1970

Malcolm Sayer was a student of aerodynamics at Loughborough University’s Department of Aeronautical and Automotive Engineering in 1938. He was one of the first designers to apply the principles of aerodynamics to cars with his scientific calculations, creating some of the most beautiful forms of the era. Sadly he died in 1970, at the relatively young age of 54.

After graduating from Loughborough he joined the Bristol Aero Company where he worked on various projects including their radial engine. One of Sayer’s colleagues at Bristol was Phil Weaver who was later to work to take charge of Jaguar’s Competition Department and work alongside Sayer on the XJ13. In an interview with Phil Weaver, Paul Skilleter (well-known Jaguar Historian and Author) recorded Weaver’s recollections of his time with Sayer at Bristol.

Malcolm Sayer joined Jaguar in 1950 and his talent was soon recognised. One of his first tasks was to design a suitable body for Jaguar’s XK120C (the “C-Type”). The chassis had already been designed by Jaguar’s Technical Director Bill Heynes. Sayer worked alongside Bob Blake who had been given the responsibility of producing a body. Sayer brought his aerodynamic skills to bear on the project and added a large element of science to the body design. He was one of the first to use wind tunnels in automotive design and photographs exists of the various small-scale models he had made to investigate the aerodynamic characteristics of his various designs.

Norman Dewis, Jaguar’s renowned Chief Tester, joined Jaguar not long after Malcolm Sayer and recalled how Sayer worked:

A number of contemporary sources cite Sayer’s habit of drawing a full-size car on the walls of his office or even with chalk on the floor. I don’t doubt that some of his initial designs for the XJ13 were done in this way. He had at least one small-scale model made up for testing before Bob Blake began the task of clothing the chassis/monocoque.

Sayer’s final designs were “formalised” as side, front, rear and plan view documents which may have become internal “standards” for his designs and used for things such as centre-of-gravity studies etc. The detail shapes of compound curves etc were established mathematically using a technique peculiar to Sayer.

Examples of these final standardised documents are shown below:

XJ13 “dimension summary”© Jaguar Heritage

In late 1967, after he had designed the XJ13, Malcolm Sayer designed three more V12 mid-engined sports racing cars. The drawing above shows one of these designs in the form of a “dimension summary”.copy; Jaguar Heritage

It is interesting to note that Sayer’s original design as shown above differs in many respects from the rebuilt “original”. It is my aim to reproduce the XJ13 exactly as Sayer had intended and before the addition of “1970s wide wheels/wheelarches” and other “updates”. It is important to me to recreate the car as close to its original specification as possible – not only to satisfy requirements for potential racing against cars of the period, but also because the historical significance of the surviving original prototype engine demands this. After all, Jaguar had always intended to produce more than one car and I feel an authentic copy could be considered to be a “continuation” in line with Jaguar’s original intentions.

Malcolm Sayer was very much a man “ahead of his time”. There is much talk nowadays of Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) but it seems that as early as the 1950s Sayer had developed his own longhand version of similar techniques. He kept his calculations and means of representing complex shapes mathematically very close to his chest and there is little information on his methodology available today.
Paul Skilleter reported that Cyril Crouch, who worked in the Body Drawing Office in Sayer’s time, recalls him “using Chambers seven-figure log tables to calculate all the shapes, as one would do on a computer now.”

Bob Blake had joined Jaguar from Briggs Cunningham and was a legendary body-builder. He was able to interpret Sayer’s data and successfully translated his drawings into the full-scale XJ13. He was joined in this task by Roger Shelbourne and Geoff Joyce. Peter Wilson also worked on the car and was responsible for making some components of the car and chassis. Wilson confirms that, contrary to popular belief, the original car wasn’t built by Abbey Panels – their involvement was limited to “the fabrication of skin panels to our formers, and roller-seam welding of the inner sill panels to the main floor and outer sill sections.”
Peter, in his book “Cat Out Of The Bag” goes on to say,

Much of this data has survived – including the precise location points of items such as suspension components, steering rack, anti-roll bars in 3D space. This data will be used in the construction of my 1966 XJ13 copy. The main difference being that technology allows us to carry out this operation on a computer screen before the actual car is manufactured.

To help achieve a faithful copy of the original design, the technique of 3D scanning coupled with digital techniques to incorporate data from period photographs, original technical drawings and eye-witness accounts is being used.
An example of how digital data can be built up from an original document (in this case an accurate drawing used in 1965 for a centre-of-gravity study) is shown below. The pictures show initial work on reproducing the original centre monocoque structure.

© Neville Swales
Not to be reproduced without permission.

© Neville Swales
Not to be reproduced without permission.

© Neville Swales
Not to be reproduced without permission.

This digital data can be supplemented and cross-referenced with original photographs, reports and original technical data – as well as the “original” prototype. Once the information has been captured, it is possible to estimate things such as weights, roll-centres, centre-of-gravity etc. It is also possible to virtually “trial-fit” components to reduce the possibility of an error during the actual build.

Once sufficient digital data has been assembled and the on-screen 3D images have been verified with photographs etc, the next step will be to use the data to produce a physical scale model using CAM techniques including the use of a 3D printer. The scale model can be painted in the correct shade of 1965 BRG (British Racing Green), handled and verified for accuracy. It also gives an opportunity to see how the light catches the car in comparison with period photographs and the current “original”. Once this has been accomplished, the digital data can be used to manufacture millimetre-perfect full-scale formers and bucks – even to the extent of pre-marked or drilled rivet locations.

As well as being able to use these powerful techniques to faithfully reproduce the original car, they can also be used to reproduce unobtainable and unique parts such as cylinder heads etc. The following picture shows this scanning technique in action on the prototype engine:

© Neville Swales
Not to be reproduced without permission.

The item to be scanned (anything from a small component to a full-size car) is covered in a non-reflective white powder. Small adhesive dots are applied across its surface and the item is laser scanned. The small dots allow the sophisticated software to locate specific points in 3D space. Internal passageways may be scanned using similar techniques using lasers on probes.

Manipulation of the resultant data and production of a final digital representation of the scanned item is a skilled operation. Once the item has been captured in this way, faithful clones can be reproduced using computer aided manufacturing techniques.

noun. Zeit·geist

… is a German word. Zeit meaning “time” and Geist meaning “ghost,” Zeitgeist means the spirit of the age or times.

Original 1966 XJ13 - MIRA 1971

The 1966 Jaguar XJ13 is no more.

Its spirit and identity live on in a Jaguar-built replica constructed from the mortal remains of the original car which suffered a calamitous crash during a demo run in 1971.

The event was a promotional exercise to publicise the soon-to-be-launched Jaguar Series 3 V12 E-Type. The venue was the high-speed banked track at the British Motor Industry Research Association (MIRA). The date was 20th January 1971.

In the words of Norman Dewis , Jaguar Test Driver, in his book "Developing the Legend

" ... "It was all the fault of the Series 3 E-Type and the new Hassan/Baily 'flat-head' production V12. The idea emerged that the new Jaguar V12 engine in the Series 3 E-Type should be launched to the press at Geneva in March 1971 amid the sight and sound of a previously unrevealed, mid-engined V12 Le Mans car emerging into sight from behind the trees. This involved getting the XJ13 out of hibernation, and as a backup to the press launch, a film would be made for wider distribution."

So it was that on 20 January 1971 a film crew from London met up with the XJ13 and Norman at MIRA.

XJ13 awoken from hibernation before that day in January 1971 Photo © Jaguar Daimler Heritage Trust

After being under wraps for over two years, the car had needed a complete check-over and, as the wheels it was on had done most of the development work, they were substituted by new wheels and tyres which had remained in the stores.”

Photo © Jaguar Daimler Heritage Trust

Break during filming Photo © Jaguar Daimler Heritage Trust

All went well at first, with a good number of laps put in at modest speeds for filming. “

“All went well at first …” Photo © Jaguar Daimler Heritage Trust

Then to conclude”, Norman relates, “I was asked if I could do four fast laps. I did three, and they were quite quick, although not as quick as I had gone in testing.”

"Then on the third lap I came onto the banking, which was the one opposite the tunnel banking where the film crew were, at about 135, and gave it full throttle to hold it in as usual. About two thirds of the way round the banking, the car lurched to the right and almost instantly went into the safety fence ..."

“... the car somersaulted off the track into the muddy field ... tyre tracks showed how the car had almost left the banked section ... then spun down the banking to end up in the field ...”

“ I was asked if I could do four fast laps. I did three, and they were quite quick ..” Photo © Jaguar Daimler Heritage Trust

The XJ13 Log Book simply states "20.1.71 Written off" at the top of the entry ..

Extract from XJ13 Log Book © Jaguar Daimler Heritage Trust

Luckily, the driving skills and lightning reflexes of the Jaguar test driver Norman Dewis meant that he survived the crash unscathed. He walked away from the crash having buried himself in the narrow confines of the cockpit. The state of the car was, however, a different matter …

The fact that the car survived at all to participate in this promotional exercise after development had ceased in 1967, was simply down to the fact that the Jaguar management felt it could play some part in promoting their production V12 engine. A memo from the late Lofty England to the late William Heynes in the September of 1967 outlines the reasons for shelving the XJ13 project as well as the justification for keeping the car in storage and not breaking it up as was the fate for many earlier projects.

“… we are about to commit ourselves for considerable expenditure with ZF for the supply of special gearbox units for the current XJ13 5-litre competition car and also a 3-litre version, which is a new project.

I feel I should point out that there now seems no doubt that the 3-litre maximum engine capacity formula for Group 6 Prototype cars will be applied to all sports car championship races, which includes Le Mans, for the next three years, i.e. up to and including 1970, which period coincides with the remaining period of the current Formula 1 racing car regulations.

There does not, therefore, appear to be any point in doing any further development work on the 5-litre car or, in fact, on a 3-litre version, unless it is our intention to produce a lightweight 3-litre Formula 1 type engine, as cars which will be competing in sports car championship races in the next three years will be in effect Formula 1 racing cars with bodywork to meet the sports car regulations. These regulations may well be amended in 1969, whereby it will no longer be necessary to provide a spare wheel or luggage accommodation, or have a specified windscreen height on open cars.

I suggest we ought to keep the 5-litre competition car as a complete unit, since we could possibly get some publicity value from it when we announce one of our production cars with a 12-cylinder engine.”

What caused the crash?

Norman Dewis confirmed that new wheels and tyres were added prior to filming. The XJ13 Log Book states these wheels were made new after testing of the car only four years earlier (late in 1967). Excepting possible manufacturing defects, it is perhaps unlikely that they could have deteriorated to the point of failure in that short space of time in storage? The use of magnesium as a constituent of alloy wheels was not a new technology in the 1960’s – indeed, magnesium wheels were used on every car that won the Indy 500 from 1946 to 1963.

When the tyres were fitted to the car’s new wheels in 1967, they were fitted without the benefit of inner-tubes. It is possible that the new tyres fitted before filming in 1971 were also fitted without inner-tubes. This, in itself, should not have caused a tyre failure. A more likely culprit may have been the unsubstantiated rumour that a rear tyre was “plugged” to prevent a slow leak before the final high-speed laps?

It is believed that the incident occurred at a speed below those attained during the short period of the car’s active development – although the speed may have been well in excess of 135mph it is unlikely the accident could have been caused by “lifting” or other “aerodynamic” reasons.

Another possibility could have been failure of a rear radius arm. Using the engine block as a stressed member, the rear wheels were mounted by a driveshaft (as upper link), a fabricated lower link and two forward-facing radius arms fixing directly to the engine mounting block. This was a rather innovative solution for the mid-1960s. Examination of the wreckage revealed a damaged upper radius rod on the rear right-hand side (offside)6. However, this damage could have been sustained during the impact. If not, a failure such as this could explain why the car “lurched to the right” before making contact with the safety-fencing at the top of the banking.

Perhaps the true facts and cause of the crash will never be known – the important facts are that the driver, the legendary Norman Dewis, and the car both survived.

What was the extent of the damage?

Except for occasional snippets of information, relatively little information has previously been made available on the development history of the XJ13 – this “vacuum” has been filled by a host of commentators/enthusiasts over the years with a range of statements and opinions – some of whom have probably never even seen the original car least of all been involved with Jaguar! As a consequence of this, an almost “mythical” status has been attached to the car. One therefore has to be careful when sifting through the “established facts”. Fortunately, at least one piece of original documentary evidence survives in Jaguar’s archive and that is the “XJ13 Log Book”. This book gives an account of the development and testing of the car including details of its post-crash examination. This document can be supplemented and cross-referenced, not only with other original surviving records, but by information from known and respected authors such as Paul Skilleter, Philip Porter, Andrew Whyte as well as surviving ex-Jaguar participants such as Peter Wilson, Mike Kimberley, Norman Dewis etc.

The XJ13 Log Book simply states "20.1.71 Written off" at the top of the entry ..

Extract from XJ13 Log Book © Jaguar Daimler Heritage Trust

In the words of Paul Skilleter in 1975 , “… there wasn’t a straight panel left on the XJ13 – a more written-off looking racing car you couldn’t imagine. It was a crestfallen party that took the remains back to Browns Lane and pushed it back into its dark corner of the development department.”

Back at Browns Lane the car was later stripped by G Gardner to assess the extent of the damage. It does seem that the damage was not as extensive as first appeared. Suspension and steering was relatively unscathed with the notable exception of the upper offside rear radius arm. Major mechanical components such as engine and ZF transaxle also survived with the only significant damage in that area being the transmission oil cooler brackets (fitted above the transaxle). However, Norman Dewis confirmed in his autobiography that the car had glanced a sand-filled oil drum as it spun towards the MIRA infield. The impact was in the offside cockpit area (the driver’s side) and Dewis’ helmet was damaged when the windscreen pillar made contact with the oil drum and hit it. This contact was further compounded by a series of end-over-end and sideways rolls.

Damage to the body/monocoque structure was extensive and these sections were beyond economical repair. The body structure of the XJ13 is entirely monocoque consisting of two wide sills (containing fuel tank-bags) which run from front to rear wheels. Between the two sills is a section of stressed floor and three bulkhead sections – two at the front and one immediately behind the driver. A further boxed section forms part of the rear bulkhead and serves to connect the sills at the rear . This entire body structure needed renewal – doors and windscreen surround included.

The two front wheels were found to be OK but both rears were broken. Incidentally, this may support the argument that a broken wheel may have been a consequence of the crash and not a cause?

What was changed during the car’s 1972/73 rebuild?

The car remained in its sorry state for more than a year. As the time for the launch of the new SOHC V12 production engine loomed, Lofty England decided the car should be restored as a promotional, rather than a competition, vehicle. I feel the car’s new status both permitted and defined changes that were made to it during its rebuild to fulfil its new role. As a consequence, certain cosmetic changes were made that deviated from Malcolm Sayer’s original design.

Ted Loades of Abbey Panels spotted the crashed XJ13 stored at Jaguar and offered that Abbey Panels would rebuild it for £1,000 - “Lofty” England accepted without hesitation ….

Luckily the original wooden bucks/formers had survived. They had been stored outside at Jaguar’s store at Radfords and had escaped the periodic “clean up” that components stored inside were subjected to.

There are many so-called “eyewitness accounts” of the damage suffered by the car and others claiming to have intimate knowledge of exactly what was damaged/replaced during its rebuild. The following represents the facts that I have been able to establish so far (further changes still under investigation):

• Completely new body/monocoque/doors built by Abbey Panels. Some of the critical dimensions were varied slightly – including the overall length and details of the rear section. A major deviation was the addition of “1970’s” wide wheelarches to enable the fitment of wider tyres/wheels. This deviation from the original design was done to improve “strength and appearance”.
• Further stiffening sections were added at the front of the car as evidenced by an additional row of rivets that appeared across the nose of the rebuilt car.
• A different means of attaching the windscreen to the surround was employed.
• The existing wheels were repaired by Jaguar and Sterling Metals. It has been suggested that new wheels were made by machining the outer section of Concord undercarriage wheels but no documentary evidence to support this has yet surfaced.
• The original light alloy radiator was found to be corroded and so a new one was made by modifying a XJ12 saloon item.
• Twin lightweight Lucas batteries were added to replace the original (which had been found to be not quite up to the job).
• The original seats were retained although retrimmed in a different material to original.
• A different style of gear-lever was used as the original had been “mislaid”.
• The car was painted in a different, lighter, shade of British Racing Green.

So … to answer the question posed earlier – “Why recreate the Jaguar XJ13?” 

Because it doesn’t exist in its original form – completely true to Malcolm Sayer’s vision…

Because there is only one car and that car is in the capable hands of Jaguar Heritage. I am unlikely to be allowed to experience the “zeitgeist” of this car and era by driving it at its limit....

Because the chances of the “original” being raced are nil – my dream is to see a recreation of the 1966 car on a racetrack racing against the cars it was designed to compete against - those from Ferrari and Ford in particular. The “original” will never race – a recreation perhaps could?….

You are invited to join me in my quest to recreate the legendary XJ13 - your contributions, support and interest will be welcomed. The journey continues!

Last month I made a post looking at the origins of the V12 – this month I look at the development of the V12 in a little more detail.

Before the V12, Jaguar’s racing and practically all road cars were powered by the powerful and renowned XK straight-six double overhead-cam unit. This engine had its origins in pencilled sketches drawn during the London blitz by Sir William Lyons and his engine designers; William Heynes (Chief Engineer), Walter Hassan and Claude Baily. These sketches and original designs were followed by working prototypes as early as 1943. The first 3,442cc production unit saw the light of day in the beautiful XK120 of 1947. The same basic engine continued production into the 1990s.

1947/1948 Jaguar XK120.

3,442cc Jaguar XK engine.

XK engine cross-section.

This engine went on to power Jaguar to a number of famous Le Mans wins. However, as early as the mid 1950s, the pace of international racing engine development led Jaguar to believe they needed to develop a successor to the XK engine to keep them at the forefront of racing. The Le Mans Sports Car Regulations at the time dictated the maximum capacity of the new engine – up to 5 litres. The Jaguar engineers agreed that the maximum power and tuning potential could be achieved with either a 8-cylinder or 12-cylinder “Vee” formation. The current XK engine had a relatively long stroke and the ability to achieve greater power by running at higher revs was compromised by this design. The XK's cylinder bore of 83mm and stroke of l06mm resulted in a piston speed of 3,820 ft./minute at 5500 r.p.m. – much faster and the engine integrity could not be guaranteed. It was decided that the future engine would have a reduced stroke of 70mm which would allow the engines to run safely up to 8,500rpm.

In around 1965, the project became reality when a number of V12 cylinder blocks and associated components were commissioned. These blocks were used to build up two types of engine – one with internal modifications made to allow a specially-modified crankshaft, lacking two “throws”, so the unit could function as a V8; the second was a full V12.

It is believed that only one of the original “V8” engines has survived. Although not salveageable and not able to be made to run either as a V8 or V12, it survives as a display model. The following picture shows this engine as it appeared in the collection of the late Jaguar collector Walter Hill in the 1980s:

V12 prototype block internally modified to run as a V8.

My previous post on the V12 made reference to the fact that, of the originally-planned eight V12 engines, only four are known to survive today. Two (Nos.1 & 7) remain with the Jaguar XJ13 Le Mans prototype, one (No.2) has survived as a complete engine and is in the process of a full restoration prior to being placed in an authentic recreation of the original 1966 XJ13. The fourth V12 (No.8) was placed in a rather inaccurate XJ13 copy – made by the well-known and talented car builder Bryan Wingfield and sold to the collector Walter Hill.

In Wingfield’s own words (as reported in “Supercar Classic” magazine) – “I got a call from somebody I knew at Jaguar who told me that there were a couple of old prototype engines lying around which were of no use to anybody else, and asked whether I was interested … I had to buy those V12s through another engineering company.”

The Wingfield copy survives today as a running car – albeit with “Ford GT40-inspired” chassis and an approximation of the XJ13 body shape. The engine itself was bought as “a box of bits” and was made up from assorted original and new parts. The most desirable feature of this engine, the only heads with the ultimate development of intake angle (41 degrees), were removed from the “Wingfield” No.8 engine some time before its sale and fitted to the No.2 engine by Jaguar in 1969 and remain with the No.2 engine to this day.

V12 prototype twin-cam engine - stages of inlet port angle development. Greatest power was developed with a 41 degree inlet angle.

V12 prototype twin-cam engine – original inlet port angle (left) and final angle (right).

It was known that a V8 configuration needs a two-plane crankshaft with wide outer crankshaft balance weights to run smoothly. A V8 firing sequence is also not as efficient as a V12 if carburettors are used. In comparison, the V12 engine has equal firing impulses along each bank and can be treated as two sets of 6-cylinder engines as far as carburation is concerned. The V12 engine is inherently smoother than a V8. As well as these technical reasons for favouring a V12 over a V8, the USA car market was very important to Jaguar. It was felt that a V12 would have greater appeal than a V8 in this market.

The first V12 prototype was assembled in 1964. The prototype engine main features were:

• Twin overhead cam per bank
• 87mm bore x 70mm stroke
• 4,991cc capacity
• LM8 (aluminium) sand cast cylinder block
• Sump face on crankshaft centreline
• Top deck with flanged split rim cast iron liners
• Seven main bearings of 3.0” diameter
• Side-by-side connecting rods offset 0.75”
• 2.187” diameter crank pins
• Forged steel crankshaft with eight balance weights
• Crankshaft lubrication end-to-end feed fed from grooves in the main bearings
• Crankpins using sludge trap system used on the XK 6-cylinder engine and transverse feed holes
• EN 4A nitrided crankshaft

The following picture shows the second engine that was assembled in 1964 – as it is today.

V12 prototype twin-cam engine – with Peter Wilson (Jaguar Competitions Department 1961-1966) – complete with ultimate development of cylinder heads.

The prototype V12 cylinder head design was very similar to the tried-and-tested XK 6-cylinder head design but with a number of important differences.

The depth of the new combustion chamber was shallower (1.03” versus the XK’s 1.30”) and the included valve angle was more narrow (60° versus 70°). The combination of shallow combustion chamber and narrower angle was theoretically more efficient.

The following comparisons were made during development:

Competition and production versions of the twin-cam engine were developed at the same time. They were all basically similar except for things such as valve and port sizes and camshafts. Ideally, the prototype engine would have employed the use of transverse inlet ports which became the norm for equivalent competition engines being built by Ferrari and B.R.M. This was found by Jaguar to be a more efficient layout for their engines but it would have been impossible to fit a V12 engine with transverse ports such as those on the XK 6-cylinder engine, with an adequate induction tract length, within the confines of an engine bay – even that of the Mk10! While the competition version was being developed, Lyons and Hassan kept in mind the need to eventually fit a version of the engine in a production car.

During development, Jaguar found that the two stage chain drive was not completely reliable and the noise level was deemed unacceptable in a sophisticated saloon car. For this reason, a partial gear-drive was proposed for the competition engine camshafts as in the following diagram:

Camshaft drive (with gears) proposed for the competition engine.

However, this arrangement was never fully developed. A single engine was completed to this specification and was run on the test-bed. However, it remained in storage after the Le Mans project came to an end and was not fitted to the XJ13 car until 1978 when a missed gear necessitated an engine change – long after the project had ceased and the rebuilt XJ13 was only used for demos etc. For all its development life, the XJ13 ran with duplex chain drive to its camshafts.

The original engines were fitted with twin distributors which were found to be troublesome. One incorporated two sets of contact breakers plus the centrifugal and vacuum advance mechanisms for both; the other was used simply to distribute the HT current. At high engine speeds difficulty was experienced in matching the timing of the two sets of contacts and the variations were deemed unacceptable.

The following picture shows the original twin distributors as still fitted to the surviving engine number 2:

Twin distributors fitted to surviving V12 prototype No.2.

As may be apparent from the picture, it would have been difficult to fit a single 12-cylinder distributor in the “Vee” and so this twin-distributor arrangement continued throughout development. Around 1973, at about the time the crashed XJ13 was rebuilt by Jaguar, they were able to modify and fit a single 12-cylinder distributor and also updated the ignition system to OPUS (Oscillating Pick-Up System). A twelve-cylinder engine running at 6000 rev/min requires a spark rate of 600 sparks/second which is well above the capability of a conventional make and break “points” system (400 sparks/second). OPUS uses an electro-magnetic pick-up and electronic solid-state switching, mechanical delays are eliminated. The prototype engines were subjected to extensive testing – not only in cars (including the XJ13) but also on the test-bed. My own engine, No.2, was also fitted to two Mk10 Jaguars. These big and heavy cars, one white and one sable, were used for road trials as the original XJ13 may have been rather too conspicuous! There are many stories surrounding these two cars including a road test by “Wilkes” of Motorsport magazine who was allowed a test drive on the understanding he never opened the bonnet to see what was inside! Retired ex-Jaguar employees also tell stories of how the cars were used to surprise and embarrass the Aston Martins being tested on the M1 motorway around Newport Pagnell …

The following picture shows this engine fitted with six carburettors for these road tests. Close examination reveals its origins as the dry sump originally fitted in 1964 (modified to wet sump for fitment in the Mk10s).

Archive photo of No.2 V12 prototype – as fitted to Mk10s.

Towards the end of the V12 project the emphasis switched from racing to powering a production saloon. This eventually led, via prototype single-overhead cam V12 engines of 6.4 and 5.3 litre capacity, to the final 6.0 litre HE engine of the mid to late 1990s.

Developments from the quad-cam racing engine to the final single overhead cam engine will be covered in a future post.

To be continued ….

I was privileged to be visited by Peter Wilson (ex Jaguar Competitions Department) who confirmed the identity of my prototype quad-cam V12 as being the second engine to have been built as part of Jaguar's quest to return to Le Mans with the XJ13.

Peter worked in the Competitions Department for five years up to 1966 and had hands-on involvement in the construction of the XJ13. Although a number of people have since claimed involvement in the project, many did not even set foot in the Competitions Department! - Peter is one of the few surviving members who can claim first-hand participation in the building of the XJ13 Le Mans prototype racer.

Since leaving Jaguar, he has worked in a number of prominent and senior positions in the automotive industry including time spent Brico Engineering, Cummins Diesel Engines and British Leyland. Since his retirement in 1999 he has written the definitive work on the Competitions Department between 1961 and 1966 including not only the XJ13, but a significant era in the racing and development of the E-Type. I can heartily recommend Peter's book "Cat Out of the Bag" which is available from Paul Skilleter books at http://www.paulskilleterbooks.co.uk/

Peter Wilson - Jaguar Competitions Department 1961-1966 with the second prototype quad-cam V12 engine

Peter is an engaging character with an absolute wealth of information on Jaguar. His straight-forward and no-nonsense account of people, places and the cars kept me absolutely enthralled during his visit. He is a very likeable person with a truly remarkable memory for the detail of past events.

I learnt a lot from Peter about my own engine - in particular:

• It is without doubt the second engine assembled by Jaguar as part of their "XJ6" (quad-cam Le Mans V12 engine) project
• It possesses the ultimate development of the quad-cam head (heads nos 18 & 19)
• The engine was fitted to two Mk10 (XJ5 Project) Cars for continued testing - I guess the XJ13 itself would have attracted too much attention! The engine was removed from the car in 1969 and then stored in the Experimental Department after a short time on the test-bed.
• The engine appears to have been untouched since being displayed at the Coventry Herbert Art Gallery & Museum in the early 1970s (engine still in the ownership of Jaguar).
• It is likely the engine was transferred to Jaguar (Germany) for display from where it was eventually sold to a member of the general public around 1980 (the engine was subsequently displayed at the Essen Motorshow in 1998 - see HERE
• The engine today remains in the same condition as when it was removed from the development test-bed in 1969 (albeit with an external cleanup for display! - the final tests carried out on the engine were to measure exhaust emissions - probably as a comparison with the later SOHC "Heron" V12 project)
• Although the engine has a wet sump (fitted when installed in the Mk10 project cars), it is a converted original dry sump.
• Although fitted with 6 x SU carburettors when installed in the Mk10 cars, the engine was initially assembled with Lucas mechanical fuel injection as the XJ13.

Peter is now engaged on writing an account of the XJ13 and we look forward to this latest book. There is so much myth and misinformation about the XJ13 that it will be very valuable to have an account written by someone who was "really there" and at the heart of the XJ13 project. For example, he was able to confirm that the XJ13 cam drive was always by means of duplex chain and certain changes made to the original car during its post-crash rebuild in 1972/73.

For now, Peter's last book, "Cat Out of the Bag" contains a whole chapter on the XJ13 with much previously-unpublished material.

On Friday, 22nd January I attended a signing of a limited-edition print of this original painting by the artist Nicholas Watts:

Nicholas' superb painting of the XJ13 at speed on the banking has been reproduced as a limited-edition of 150 high-quality, giclee prints. They will soon be available for retail sale (contact Trevor Wilson of TWR Replicas for details).

Following a rendezvous around the XJ13 on display at the Jaguar Daimler Heritage Trust's museum at Coventry, the signing took place in the JDHT boardroom.

The event was organised by Trevor Wilson of TWR Replicas - suppliers of the XJ13 replica in the UK. Each print was signed by Norman Dewis (Jaguar test-driver), Mike Kimberley (current CEO of Lotus and a member of the XJ13 design team), Peter Wilson (author of "Cat out of the Bag" and also a design team member) and Peter Jones (design team member).

Left to right .... Peter Wilson, Peter Jones, Mike Kimberley, Norman Dewis

Norman Dewis

In a career spanning 33 years at Jaguar, Norman Dewis tested and developed a remarkable series of cars including:C-type, D-type, XK 140/150, 2.4/3.4 and Mk 2 saloons, Mk VII/Mk VIIM, E-type, XJ13, XJ/XJ-S and XJ40. Plus, he rode with Stirling Moss in a C-type in the 1952 Mille Miglia, drove a 190mph works D-type in the highly dramatic 1955 Le Mans, raced in the Goodwood 9 Hours, and set an amazing 173mph production car record at Jabbeke in Belgium with an XK 120. Completing over a million test miles at 100mph-plus average, Norman also played a crucial role developing the revolutionary Dunlop disc brake, and survived high-speed crashes and rollovers in the days before seat-belts – and without ever breaking a single bone.

Mike Kimberley

Michael J. Kimberley (“Mike”) C.Eng., F.I. Mech. E., F.R.S.A., F.I.E.D, F.I.M.I has had a remarkable career in the motor industry over the last 56 years, working with some of the great engineers, innovators and leaders of the worlds motor companies. Mike started as an apprentice with Jaguar in 1953 before rapidly progressing to becoming in Section Leader, Special Projects at Jaguar in 1965 where he lead the team developing the Jaguar XJ13 Le Mans car, under such famous names as Jaguar founder Sir William Lyons and Jaguar race director Frank (Lofty) England. In 1969, he joined Lotus as Manager of Continuous Engineering, with the Lotus Europa Twin Cam being one of his most notable projects. Mike rose steadily but rapidly through the Lotus ranks, joining the Board of Lotus aged 37, and becoming Managing Director of Lotus Cars in 1976 and Managing Director of Lotus Engineering by 1980, being responsible for such Lotus icons as the Esprit, Eclat and Elite.

During the 1970s and 80s, Mike had the unique experience of having worked closely with the company’s founder Colin Chapman, with whom Mike set up the world class Lotus Engineering consultancy to enable Lotus to work for many other cars companies around the world. Lotus Engineering is now a globally recognised high technology engineering consultancy and serves many of the world’s car companies. After Colin Chapman’s tragic and untimely death in 1982, Mike became C.E.O of Group Lotus plc, as well as holding board positions with a number of Lotus associated companies such as Chairman of Millbrook Proving Ground and President of Moog Systems Inc. With Lotus under General Motors ownership, Mike became Chairman of Group Lotus plc before leaving Lotus in 1992 to become Executive Vice President (General Motors Overseas Corporation) based in South East Asia. Two years later, Mike became director of the Vector Aeromotive Corporation, and in 1994, he became President & Managing Director of Automobili Lamborghini S.p.A, being responsible for the rebuilding of Lamborghini after Chrysler’s ownership and prior to its sale to Audi AG, as part of the VW Group. In the mid 1990s, Mike left Lamborghini and worked directly for Tommy Suharto as a board member of Timor Putra Nasional (owners of Lamborghini) until retiring with an undiagnosed tropical fever. Returning to the automotive industry a few months later, Mike worked in a consultancy role for a number of organisations including Tata Motors Ltd. In August 2005 Mike was appointed to the Lotus Group International Limited and Group Lotus plc Boards as well as other Boards of Proton. He was appointed acting Chief Executive Officer of Group Lotus plc in May 2006, confirmed as Chief Executive Officer of Group Lotus plc in September 2006. During his second tenure at Lotus, Mike has been responsible for the creation and execution of a new 5 year strategic business plan, and the new, already award-winning Lotus Evora is the first of the range of new Lotus cars to be designed, developed, manufactured and sold by Britain’s most iconic and innovative sportscar company. Lotus Engineering has expanded to become a world-class consultancy employing over 500 highly qualified engineers in five technical centres around the globe. It is revered for innovation, outstanding driving dynamics, exciting niche vehicles and efficient performance engineering. Mike (70) is married with 3 children and 3 grand children and lives in Norwich.

Peter Wilson

Peter Wilson began his career at a small Carlisle garage but in 1961 embarked on an engineering apprenticeship at Jaguar. Within two years he had progressed to the company’s competition department where for over five years he was involved in a multitude of exciting projects - E2A, the new works competition car * The Mk 2 GT saloon * the four-seater E-type * the E-type goes racing * the Mk X convention * building the lightweight E-type * E2A and Maxaret brakes * the 2+2 E-type * the Cunningham Le Mans E-type * Bob Blake and the S-type * * the Coombs power boat * racing 4 WPD * E-type works tuning booklet * XJ13. Peter knew many of the Jaguar ‘giants’ including Bill Heynes, Malcolm Sayer, Bob Blake and Harry Mundy.