Jaguar XJ13 – Malcolm Sayer’s Crowning Glory

Building The Legend Limited

“Sayer uniquely blended science and art to produce timeless shapes of exceptional and enduring beauty. He brought science to the art of car design; and scientifically produced works of art.”

21st May 2016 marked the Centenary of the birth of one of this country’s greatest design geniuses. Malcolm Sayer was taken away from us at a relatively young age when he suffered a fatal heart attack, outside Parkside Garage, next to the Regent Hotel in Royal Leamington Spa, 1 month before his 54th birthday.

His legacy is a collection of iconic Jaguar Sports Cars – C-Type, D-Type, E-Type and the sublime XJ13 – the latter being his crowning achievement.

1966 to 2016 – 50 Years

Coinciding with his birthday, the first public “reveal” of my recreation of Sayer’s 1966 XJ13 took place at the London Classic Car Show at the Excel in London. The car is my personal tribute to this great, and perhaps under-appreciated, man whose final resting-place is unknown – even today.

The car replicates Jaguar’s XJ13 as it first left Jaguar’s Competition Department – as Malcolm Sayer envisaged it and before it was crashed and re-skinned in 1972/73.

At the end of 2014, the bark of Jaguar’s legendary No.2 quad-cam V12 engine was heard for the first time in 50 years. The starter was pressed by the same Jim Eastick who started the No.1 engine for the first time in 1964 in the presence of Jaguar’s Bill Heynes – this time, in the presence of Jonathan Heynes, son of the late Bill Heynes.

1916 to 2016 -100 Years

Just over 100 years ago, Gilbert and Annie Sayer became parents to a son they named Malcolm. Malcolm Sayer – a name which was to become synonymous with Jaguar’s classic and most beautiful iconic designs. Malcolm’s birth in 1916 no doubt represented a bright spot in the otherwise dark times during the middle of the First World War in that eastern corner of the UK – Cromer, Norfolk. Malcolm’s father, Gilbert, was a teacher at Great Yarmouth Grammar School where he taught the unusual combination of Maths and Art – certainly a man whose interests would have influenced the direction his son’s career was eventually to take.

Malcolm’s birth, preceded by a German Zeppelin attack on the Eastern Coast of the England, coincided with the introduction of UK Daylight Saving on the 21st May 1916. Cars were relatively few and far between on Norfolk roads with most being made by the Ford, Rover, Wolseley, Morris and Humber car companies. Smaller-volume manufacturers such as Crossley also had offerings. The kind of cars on Britain’s roads around the time the infant took his first steps were similar to those pictured below – a far cry from the designs later to emerge from his pen!


Malcolm’s Grandson, Sam (Founder of The Malcolm Sayer Foundation) takes up the story:

“From the start he was interested in maths art and science, and despite many childhood illnesses, he was a high academic achiever and gained the prestigious Empire Scholarship* at the early age of 17. This enabled him to attend the then Loughborough College, where he gained a first class honours diploma in Automotive Engineering. He was also Secretary of the College motor Club and for two years Editor of the College Magazine.

After graduation, Malcolm joined the Bristol Aeroplane Company, studying aeronautics and looking at ways of improving the efficiency and design of significant WW2 aircraft, particularly the Blenheim and the Beaufighter; and developing his expertise in aerodynamics as applied to mechanical design. Following the war he married Pat Morgan in 1947 and after his daughter Kate was born in 1948 he went to Iraq to work at Baghdad University. This turned out to only exist on paper, so he worked instead maintaining the fleet of government vehicles.”

*The “Empire Scholarship” referred to above were open to all British subjects living in any part of the Empire. These scholarships awarded the sum of £75 per annum which helped Malcolm complete his studies at the Faculty of Engineering at Loughborough College.

The pictures below show students working using Loughborough College’s wind tunnel during Malcolm Sayer’s years (pictures reproduced with permission from Loughborough University): 

Wind Tunnel – c1936 © Loughborough University
Wind Tunnel – c1936 © Loughborough University
Wind Tunnel – c1936 © Loughborough University

Malcolm Sayer – Aerodynamic Wizard

A few years ago the BBC recorded a tribute to Malcolm Sayer. The program was aired on Radio 4 and presented by Jonathan Glancey. Contributors included Sir Stirling Moss, Lord March of Goodwood, Philip Porter, Peter Wilson, Kate Sayer (Malcolm’s daughter), Jools Holland, Norman Dewis, Mike Kimberley, Mick Walsh and Yours Truly. The following video adds pictures to the radio broadcast:


Malcolm Sayer graduated from Loughborough College and joined the Bristol Aeroplane Company on the 22nd September 1938.

According to our friends at Wikipedia …

“The Bristol Aeroplane Company, originally the British and Colonial Aeroplane Company, was both one of the first and one of the most important British aviation companies, designing and manufacturing both airframes and aero engines. Notable aircraft produced by the company include the ‘Boxkite’, the Bristol Fighter, the Bulldog, the Blenheim, the Beaufighter, and the Britannia, and much of the preliminary work which led to the Concorde was carried out by the company.”

A few years later there was to be a tenuous link between Malcolm and Jaguar as Norman Dewis OBE was to fly as gunner in Bristol Blenheims. I wonder if Norman and Malcolm ever discussed this when they met up at Jaguar years later?

The Mysterious German

Sayer, by virtue of having a “reserved occupation” at the Bristol Aeroplane Company, was spared National Service during WW2. Instead, he put his skills to good use helping design warplanes and their engines for the Allied war effort. He married Patricia at the end of hostilities. Patricia gave birth to their first daughter, Kate, in 1948. I am sure Kate won’t thank me for mentioning the date … 😉 Malcolm and Patricia later extended their family with another daughter (Mary – 1956) and a son (John – 1953).

Kate Sayer
Malcolm’s First Daughter

In the same year as Kate was born, Malcolm was asked to establish a Faculty of Engineering at Baghdad University. He duly arrived in Iraq only to find the opportunity to create the Faculty didn’t exist! His time wasn’t wasted however and he instead spent a few days alone in the desert by a German Mathematician. he was later joined in Iraq by his wife and new daughter.

Malcolm learnt from the mysterious German and used his teachings to develop his own unique way of defining complex shapes in a purely mathematical way – much as we do nowadays using CAD and computers. He always kept the details of exactly how he did this very close to his chest.

Ex-Jaguar Competition Department and Author Peter Wilson described Sayer’s way of working as follows in his book, “Cat Out of the Bag” (no longer in print):

“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 curved surface definition by a German, when they spent a few days together in a tent in the desert ….

… It was a system which was relatively easy to use: just a case of marking out the points defined by the coordinates on a sheet of plywood, cutting it out, then assembling each piece relative to its datum on a wooden base and ‘hey presto’, you had a complete skin former …

… Malcolm kept his method of mathematically calculating complex curved surfaces very close to his chest …”

A Legacy

Malcolm Sayer has left us with some of the most beautiful examples of sporting automotive design the world has seen.

Even today, at Jaguar, the essential elements of his designs can be seen in cars such as the C-X75. Jaguar’s concept (which may see production) unashamedly draws on its styling cues from Sayer’s XJ13. Check out the following pictures and video:

© Building The Legend 2016
© Building The Legend 2016
© Building The Legend 2016
© Building The Legend 2016
© Building The Legend 2016
© Building The Legend 2016

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.

Monticello Motor Club, NY

Building The Legend, XJ13, Neville Swales, Jaguar, LM69, Ecurie Cars

First outing in anger for our full-race 6.8-litre SOHC V12 re-creation. Stretches its legs in the capable hands of Robillard Racing team owner and driver – Joe Robillard.

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.

1966 Le Mans – Ford vs Ferrari …. vs Jaguar?

XJ13, Building The Legend, Neville Swales, 1966 Le Mans - Ford vs Ferrari .... vs Jaguar?

Original XJ13 – Would it have been competitive?

In my opinion?

Yes. Let me explain …

How did the competition look?

When I scan through reports, analyses and tests, Jaguar clearly had two cars in its sights – Ferrari’s 330 P3 and Ford’s GT40.

Ferrari P4

In 1964 their eyes will have been on a 1966 Le Mans debut for a team of XJ13s. These cars would have raced as Le Mans Prototypes. In the spring of 1963, Ford heard that Enzo Ferrari was interested in selling his company to Ford. Ford committed millions of dollars researching and auditing Ferrari’s company only to have Ferrari unilaterally withdraw from talks at a late stage. This angered Henry Ford II who directed his racing division to find a company that could help them build a Ferrari-beater on the world endurance-racing circuit. The Ferrari-beater turned out to be the GT40


which, although American-built, was based on a collaboration between Ford and England’s Lola. Ford did not, at this time, have the racing prowess to take on the likes of Ferrari so had earlier engaged in discussions with England’s Lotus, Cooper and Lola – eventually choosing the latter as a partner. The first GT40s raced in 1964 and 1965 with no great success. In 1966 however the 7-litre Mk II absolutely dominated the 24 Hours of Le Mans race with a 1-2-3 result – shades of the Jaguar victories in the 1950s. This dominance continued in 1967 with a win by the Mk IV version of the car.The Lucas Mechanical Fuel-injected 1966 Ferrari 330 P3 used a rather fragile transmission that was later replaced by a ZF. Jaguar’s design included Lucas Mechanical Fuel Injection and the more robust ZF DS25-1 transmission from the outset. In 1967 the P3 became the P4. The latter car finished 2nd and 3rd at Le Mans in 1967 behind the winning Ford GT40 Mark IV.

How would the XJ13 have fared against the mighty GT40?

Project delays and lack of commitment by Jaguar meant things got off to a slow start and the car wasn’t completed until 1966. Sadly, the car’s main opportunity to shine at Le Mans may have been missed.Although Jaguar’s rebuilt “original” will probably never race, my car perhaps could. However, even though I can recreate a car with similar power and identical handling characteristics to the 1966 original, it would probably be humbled by a GT40 if it lined up against it on a track today. The reason being that, since 1967, original GT40s have undergone continuing race development and are probably now achieving levels of handling and performance far in excess of those achieved in 1967. The Jaguar XJ13 hasn’t enjoyed the best part of 50 years continuous development and would likely be embarrassed if placed on a track alongside an original GT40 today.This would definitely be true of Jaguar’s one-and-only rebuilt “original” which has led a sheltered life punctuated only by the odd low-speed excursion and short run over the last 50 years since it was rebuilt as a “demo queen”. In performance terms, the engine powering the “original” is only a shadow of its former self and would likely struggle to maintain any sort of pace.

As a lasting homage to the genius of its late designer Malcolm Sayer, Jaguar’s rebuilt “original” does continue to inspire with its superb lines but is likely to remain as no more than an inspiration.

However ….

We can at least examine the many contemporary records and reports that have recently come to light. We are fortunate in being able to re-live events through things such as the detailed development and testing reports recorded at the time. The XJ13 Project Manager, Mike Kimberley fortunately recorded events in detail through his meticulous test reports and worklists that were prompted by post-test analysis. A then-current GT40 was acquired by Jaguar’s Competition Department in 1966 and the results of their findings were also recorded.

In addition ….

Readers of this blog will know of my intention to not only recreate the XJ13 exactly as it was in 1966 but also to eventually see it on a racetrack. I am taking great (some would say “obsessive” ) care to remain true to original suspension design/location so that my recreation should perform similarly to the 1966 original. The finished product may give us additional insight into how the original may have fared in competition. Watch this space!

“Jaguar’s GT40”

By the middle of February 1966, the XJ13 was nearing completion. With all eyes on the likely competition at Le Mans in 1967, “Lofty” England (Jaguar’s racing team manager) succeeded in borrowing a Ford GT40 from Ford Advance Vehicles. It was duly delivered to the Competition Department where it was subjected to a detailed analysis. Mike Kimberley, Derrick White and Malcolm Sayer were very much involved in this analysis of the “competition” and participated in its stripdown, measurement and analysis. Someone else also involved in this analysis was Peter Wilson – author of the definitive work on the XJ13, “XJ13 – The Definitive Story of the Jaguar Le Mans Car and the V12 Engine that Powered it”.

The car Lofty borrowed wasn’t a racer but a road-going version powered by a 4.7 litre wet-sump engine.According to Peter Wilson:“Touring equipment in the form of ‘luggage boxes’ were fitted either side of the engine compartment, adjacent to the exhaust manifolds. We felt these were good for very little else other than keeping one’s fish and chips warm on the way home from the chip shop! This car, road registered OVX 355D, sat on wire wheels and was painted silver, while the cockpit was fully-trimmed and featured a driver’s door mounted, push-button Motorola radio, together with a twin speaker system – sheer luxury on wheels!”Has this car survived? Perhaps any GT40 enthusiasts could please let me know?The car was taken to MIRA on 4th March 1966 by Mike Kimberley & Norman Dewis and the car was put through its paces. Testing wasn’t particularly extensive as the car wasn’t a full race version – in any case, time was running short!In his book, Peter Wilson gives an account of the MIRA test. Bearing in mind Norman Dewis had comparison with the XJ13 in mind, in summary:

  • Despite being a “road car”, the general handling characteristics were very good and the car was responsive with sensitive and positive steering.
  • There was low-speed understeer which only changed to oversteer at maximum power.
  • The car was very susceptible to being blown off course in conditions of changing wind direction – requiring correction to maintain course.
  • Maximum cornering force was just less than 1G.
  • Whilst smooth, even braking could be achieved, it was not possible to lock the wheels. The pads hadn’t been fully warmed for these tests however.
  • The maximum lap speed was found to be 133mph which compared poorly with the D-Type’s 155mph – highlighting the “road-car” spec of this GT40.
  • Even though the car was et up for the road, ride refinement was lacking with a hard ride and “kicks” from the steering.
  • Static geometry checks showed the car had been quite badly set up with a 1″ difference in track front-to-rear (both should have been 54″).
  • The gearchange for the DS25-1 transaxle was found to be light and easy to use (as was the case with the XJ13). I’ll let you know in due course!
  • Pedal spacing was ideal and made “heeling-and-toeing” very easy. The accelerator pedal was a pendant type wheras the XJ13’s was organ type.

After the driving tests, the car was taken into the MIRA wind-tunnel and Malcolm Sayer was able to examine the car’s airflow characteristics in some detail.Sayer noted differences between the car and its racing version including blanking-off of brake ducts and side-cooling ducts. He also noted the rear spoiler was a good 4″ shorter than the 1965 car and the car didn’t have the lift-reduction deflector plates which would have increased drag.Although drag for the road-car was lower than the 1962 E-Type and 1962 Ferrari Berlinetta, it was significantly worse than the 1955 racing D-Type. Aerodynamic lift did seem to be an issue and it was interesting to note that “reliable sources” stated Ford were suffering with excessive lift on their racing versions. These “reliable sources” may have been from MIRA who were carrying out secret air-studies for Ford at the time.It was interesting to see that the XJ13 (which was almost complete at the time these comparisons with the GT40 were carried out) had many similarities to the GT40. Two completely disparate teams of individuals working towards a common goal – success at Le Mans – ended up with very similar solutions. For example:

  • The Ford famously was just over 40″ high wheras the XJ13 was lower at just under 39″
  • Wheelbases were within an inch of each other (Ford 95″; Jaguar 96″)
  • Tracks were similar (Ford 54″; Jaguar 56″)
  • Width (Ford 70″; Jaguar 71″)
  • XJ13 had similar but smaller frontal area (Ford 16.91 sq ft; Jaguar 15.97 sq ft)
  • XJ13 had similar but superior drag (Ford 0.35; Jaguar 0.29)
  • XJ13 was lighter (Ford 2,707 lbs; Jaguar 2,600 lbs)
  • Lower centre of gravity for the XJ13 (Ford 15.02″; Jaguar (14.5″)

XJ13 – Tested at Silverstone

The XJ13’s main test driver was David Hobbs. Although Jaguar already had a competent driver in the shape of Norman Dewis, William Heynes recognised as early as 1964 that a car such as the XJ13 really needed a top-flight race driver to help develop it. There is some evidence to suggest that Jack Brabham had been approached in this respect but, in the end a former Jaguar apprentice – David Hobbs – was recruited for testing. In 1969 Hobbs was included in a FIA list of graded drivers which was an élite group of 27 who were rated the best in the world. It was Hobbs who achieved the unofficial UK closed lap record with the XJ13 which stood for the next 32 years. The XJ13’s main test and development driver, Hobbs, was joined at Silverstone for the XJ13’s final test at full racing speed by another top-flight racing driver (and ex-Jaguar apprentice) Richard (“Dickie”) Attwood.On the morning of Tuesday, 15th August, the XJ13 was taken to Silverstone amidst great secrecy. Mike Kimberley planned for David Hobbs to drive all that day for comprehensive testing under full racing conditions. They wanted to see what the XJ13 could do! Unfortunately, rain began to fall (this was an English Summer after all) and testing was curtailed early on. Conditions looked better the next morning and David Hobbs was joined by Richard Attwood. Although drying, the track was still wet in places and the XJ13 gingerly took to the track. Conditions continued to improve although a shower did interrupt proceedings for two hours and some dampness did remain at the end of testing. Hobbs and Attwood managed a full five hours of testing – although they had to seek shelter for two hours during the shower.Hobbs did outperform Attwood. Mike Kimberley later described Hobbs as “a fearless driver” who clearly drove with maximum commitment. Hobbs had also carried out the lions’ share of testing and so was very familiar with the car already. His best time was a respectable 1 minute 35.7 seconds – this on a drying track with a lingering damp patch at Beckets. A time comparable to Attwood’s previous best time in a Ferrari LM of 1 minute 35 seconds – the same time as the best time for a GT40 in the hands of P. Hawkins (1 minute 35 seconds).The test at Silverstone was to be the final outing for the XJ13. It was never to race and only emerged when required to play a supporting role in a promotional film in 1971 for the soon-to-be-launched Series 3 V12 E-Type. It crashed and was rebuilt in 1972/73 in a specification more suited to its role as “demo” vehicle. It has now been established that the crash was caused by the failure of a rear tyre that had been plugged to cure a slow leak – Norman Dewis having ignored instructions not to drive at racing speeds for the camera.

Would the XJ13 have been competitive at Le Mans?

After the Silverstone test, the data was examined and a package of improvements was proposed which may have delivered the following:

  • Improved brakes – an improvement of 2 to 3 seconds
  • Lower axle ratio – a further 1/2 to 1 second
  • Improved tyres/wider wheels – 2 seconds

The above, conservative, estimates would have resulted in a Silverstone lap time in the region of 1 minute 30 seconds. A full five seconds faster than the best lap time achieved by P Hawkins before 1967 and coincidentally, similar to Hobbs’ best lap time in a BRM V8 F1 car at the British Grand Prix in 1967 at Silverstone.The XJ13 was designed in 1964 by a small team of people under Bill Heynes – Malcolm Sayer, Derrick White and Alex Frick. At the same time, they were working on a number of actively-campaigned E-Types. This team was incredibly small considering their workload (even Connaught had a design staff of 8 in 1955!).In 1964 they settled on a monocoque design using Baily’s quad-cam V12 as a fully-stressed member – like the D- and E-Types before it, a more sophisticated and advanced design than its contemporaries. By the end of 1964 they had settled on the basic layout of the rear suspension. In essence, similar to the E-Type with a lower wishbones and a fixed-length driveshaft acting as upper link. White, argued for a transverse upper suspension link coupled with a sliding driveshaft. This would have ensured greater accuracy in controlling rear wheel geometry when faced by the demands of tyres rapidly growing in width at the time. His wishes were constantly rejected by William Heynes.Derrick White also designed a series of completely novel state-of-the-art front suspension setups. Heynes, it seems, from the outset wanted to adopt an E-Type based setup. Each of White’s designs were rejected by Heynes in turn. He also became increasingly frustrated at Heynes’ lack of progress and stubborn attitude. In the end White became royally pi**ed off with all this and left Jaguar to join Cooper.Shortly after joining Cooper (and having been given free reign to design a car in the way he felt it should be designed) his Cooper-Maserati became a front-runner in the 1966 F1 season then won the first race of the 1967 season. He later joined the Honda/Lola/Surtees consortium and helped design the “Hondola” wich won first time out in 1967.It is a shame he was prevented from exercising his talents on the XJ13 as well as the lack of urgency throughout 1965 as Ford may really have been humbled by the XJ13!

What do you think?

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.

Today in the Workshop …..

Today in the workshop …

Original 1966 Jaguar V12 Prototype Quad-Cam Engine …. Street-Legal re-created XJ13 …. polished XJ13 in progress … “Building The Legend” Quad-Cam 7.7-litre V12 …. Lightweight E-Type front suspension ….

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.

Four car tribute to honour Norman Dewis OBE at The Classic Motor Show

Ecurie Cars
Image: Classic Driver

The Jaguar Enthusiasts’ Club will be paying tribute to legendary Jaguar test development driver, Norman Dewis OBE at the show with the special four-car display (see below), supplied by the Jaguar Daimler Heritage Trust and held at the NEC over the weekend of 8-10th November 2019. They celebrate the story of his Jaguar career alongside an exciting new car from Ecurie Ecosse, the LM69 which represents a contemporary evocation of one the most famous cars Norman Dewis worked on.

Norman Dewis, who passed away in June 2019 at the age of 98, was a hero to Jaguar fans and a friend to many in the classic car community. He was chief test driver and development engineer for Jaguar between 1952 and 1985. That 33-year career with Jaguar saw him break the land speed record for production cars in a Jaguar XK120 on the Jabbeke Highway in Belgium in 1953 and, through his long and often dangerous hours of test driving, significantly contributed to the Le Mans wins for Jaguar in the 1950s with the C and D – Types. Norman also raced alongside the greats which included Moss, Hawthorn and Fangio behind the wheel of a works Jaguar D Type.

Norman’s development career spanned the XK140 and XK150, the Mark 2 saloons, the E Type and the first XJ saloon through to the XJ40. In 2014, the adoration of Norman’s fans was recognised on a national scale, when he was awarded the Order of the British Empire (OBE).

The Jaguar Enthusiasts’ Club, with the support of the Jaguar Daimler Heritage Trust and Ecurie Ecosse, has assembled a line-up of four cars that represent key moments in Norman’s career. The prototype Jaguar D Type, the motor show E -Type that he famously drove through the night to Geneva, the unique XJ13 that he developed and was lucky to escape a crash in – all represent key moments in Norman’s life. Furthermore, the lasting legacy of the development work that Norman put into the XJ13 can be seen with the debut at the show of the new Ecurie Ecosse LM69, based on the original XJ13.

Furthermore, throughout the weekend, the club will share interviews and talks from club members, historians, authors and others who knew Norman, to share memories and stories of the much-admired test driver.

James Blackwell, General Manager of the Jaguar Enthusiasts’ Club says, “Our Jaguar loving community has lost a dear friend, colleague and hero in Norman. His stories captivated and inspired us all in the club and he was wonderful company, a man who never took his foot off the gas. It felt important to everyone in the Jaguar Enthusiasts’ Club to say goodbye to our hero by working with our friends at Jaguar Daimler Heritage Trust, who have supplied this stunning line up of cars. With their help, we will transform our car club display stand at this year’s NEC Lancaster Classic Motor Show with Discovery, into a tribute to Norman’s incredible life.”

“We are really excited to premiere the Ecurie Ecosse LM69 at the show, a stunning new car, guaranteed to create a stir. We felt that the LM69 is a great embodiment of the lasting legacy of Norman’s work on the XJ13 back in the 1960s.”

Norman Dewis OBE was a one of a kind. He came from an era when racing and test drivers alike were heroes. When the boundaries of technology and engineering were pushed aside and broken through, whilst wearing a shirt and tie. Norman was one of the most highly respected drivers and engineers that has ever lived, he had a special talent for assessing the handling of car and how it might be improved. He was tenacious and hard working with an enviable determination to achieve and exceed the goals that Jaguar set for him. The likes of Norman Dewis will never be seen again, so come and join the Jaguar Enthusiasts’ Club at the 2019 Lancaster Classic Motor Show with Discovery to celebrate the life of the friend, hero and inspiration to Jaguar fans everywhere, Norman Dewis OBE.

The cars in detail

Source: Octane Magazine
Jaguar D Type – OVC 501

Source: Octane Magazine

Jaguar D Type – OVC 501
The first car in the line-up will be Jaguar’s prototype D Type, OVC 501 from 1954. This is a truly unique car and is the factory prototype for the machine which brought Jaguar a hat-trick of victories from 1955 to 1957 thanks, in large part, to the development work and testing undertaken by Norman Dewis. Norman put the car through a rigorous programme of tests in which he found problems with the engine, gearbox and steering, all of which were quickly rectified. Capable of 190mph on the circuit, this car was also driveable on the road, which Norman did, as all the works cars were driven from Coventry to Dover, onto the ferry, and then down public roads to the Circuit De La Sarthe, Le Mans.

Source: Jaguar Belgium
Jaguar E Type – 77RW

Jaguar E Type – 77RW
In March 1961, an icon was launched at the Geneva Motor Show, the Jaguar E Type. This car is the subject of one of Norman’s most famous stories. Norman drove it out to Geneva from Coventry, non-stop through the night, to satisfy the unprecedented demand for press test drives at the motor show launch. The epic trip, saw him embark upon a dramatic 12-hour overnight endurance run, making it in time for the launch at 10 am the next morning. 77 RW is now the oldest surviving open E-types and was the car that launched one of the symbols of 1960s motoring. Most recently, the car was the wedding transport for Pippa Middleton’s marriage to James Matthews.

Source: Classic Driver
Jaguar XJ13

Jaguar XJ13
There was only ever one XJ13 ever built and it will be on display as part of the Jaguar Enthusiasts’ Club tribute to Norman Dewis. It was built as a contender to the likes of Ferrari and Ford at Le Mans, but never it raced. XJ13, which was Jaguar’s first mid-engined car, spent four years sitting under covers at the factory after development was canned due to a change in the motor sport regulations. However, in 1971 it was used in a film for the E Type V12 launch, shot at the MIRA test track. Naturally, Norman Dewis was at the wheel, but as he was coming in after filming, the car suffered a puncture on the banking which sent it crashing into the track’s retaining fence. It was a spectacular accident, resulting in Norman flipping end-over-end twice, rolling twice, then landing back on his wheels. Ever the professional and never strapped in, Norman managed to hide under the scuttle and turn off the ignition and as a result, was lucky to survive. He not only escaped unhurt but was also back at work the very next day! The car was later rebuilt and retired to a gentler life.

Source: Design Q
Ecurie Ecosse LM69

Ecurie Ecosse LM69
Fifty years on from the completion of the XJ13, the legacy of the car that Norman helped to develop lives on in the incredibly exciting new LM69, by Ecurie Ecosse. Launched in September, this will be the car’s first ever appearance at the Classic Motor Show held at the NEC Birmingham. Ecurie Ecosse will only be hand-building 25 in Coventry, in keeping with the FIA Homologation requirements of 1969 for running prototypes at Le Mans of over 3000cc. The “Building The Legend” quad-cam V12 is the heart of the car, designed to evoke the experience of driving at Le Mans. However, unlike the original XJ13 – this is fully road legal. Ecurie Ecosse have developed the car to a strict and unique brief which saw them adhering to the regulations of 1969, featuring only design details and technology that entered motorsport at that time. Composite materials have been used, it’s lighter than the original XJ13 and it boasts experimental aerodynamic devices, wider wheels and a multitude of engine improvements. This is a great opportunity to see this new, exciting car that celebrates the legacy of the XJ13 and the work of Norman Dewis for modern times on the Jaguar Enthusiasts’ Club stand.

Ecurie Cars Logo.png

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.

David Hobbs – Jaguar XJ13’s Test Driver

David Hobbs

Hang on – I thought Norman Dewis was the XJ13’s test driver?

Noooo …. a common misconception but, in truth, the legendary Mr Dewis did not participate in all the tests. Contrary to popular belief, there were no “unofficial” tests and the car was driven at all of its outings during active development by David Hobbs. It is believed the car was never taken to Bruntingthorpe or, indeed, any other venues besides MIRA and Silverstone – again, despite claims to the contrary. Hobbs was joined on some of the occasions by Norman Dewis but the latter was entirely absent during the culminating high-speed trials at Silverstone in 1967 where Hobbs was paired with race-driver and former apprentice Richard “Dickie” Attwood.

Four years after the end of the project, the car was driven by Norman Dewis at MIRA to help publicise Jaguar’s forthcoming V12 E-Type but the results of that particular outing are well-documented … here and here

From the outset, Jaguar realised that a car such as the XJ13 called for experienced racing drivers to assist with testing and development. There is evidence that William Heynes (Jaguar’s Chief Engineer) approached Sir Jack Brabham early in 1965 as evidenced by the following letter:

Letter from Jack Brabham to William Heynes conforming his willingness to assist with “high speed testing” of Jaguar’s new sports car. The “new sports car” in 1965 can only have been the XJ13 on which manufacture was about to commence.

In the end, Jaguar called on the services of former Jaguar apprentices David “Hobbo” Hobbs and Richard “Dickie” Attwood. In Lofty England’s own words (as published in the February 1993 edition of “Jaguar Driver” published by the Jaguar Drivers’ Club):

Lofty England of Jaguar
“Lofty” England

“… I strongly doubt if Mike Kimberley who was in charge of the XJ13 project took the car to MIRA for Dewis to test contrary to Sir Williams’ orders, possibly Bill Heynes had not informed Kimberley … we tested the car at MIRA … with David Hobbs driving and then took it to Silverstone where my old friend Jimmy Brown who ran Silverstone ensured there were no watchful eyes. We used David Hobbs for the MIRA tests since he had considerable experience of driving large-engined mid-engined cars in Cam Am races and for the Silverstone tests also used Richard Attwood both ex Jaguar apprentices and very experienced Le Mans Drivers. By the time these tests were made the car was some years old in which time there had been considerable development with tyres, brakes and suspension and to have made the car really competitive a lot of re-design would have been necessary so having learnt a lot the car was “put on ice”.

When we were about to introduce the Series 3 E-Type with V12 engine a short film was being made covering the development of the V12 engine and I was asked by Andrew Whyte to permit the use of the XJ13 to produce the right sort of background noise – that lovely-sounding V12 engine. I agreed on the very clear understanding that no high-speed running would be involved – all that was necessary was to go past the microphone at not more than 100mph using a low gear and high rpm.

I think that Norman Dewis had probably been put out by us using David Hobbs who had gone very quickly at MIRA and decided that he would see how fast he could get round – against my instructions. In doing this he hit one of the posts at the top of the banking which indented the body below the wheel hub line starting at the front of the rear wheel arch and taking a piece out of the rear wheel rim after which the tyre went flat and you know the rest …”

So just who is this David Hobbs?

David “Hobbo” Hobbs

David’s Wikipedia entry reads:

“David Wishart Hobbs (born 9 June 1939 in England) is a British former racing driver. Originally employed as a commentator for the “Speed” Channel, he currently works as a commentator for the NBC Sports Network. In 1969 Hobbs was included in the FIA list of graded drivers, an élite group of 27 drivers who by their achievements were rated the best in the world.”

But there is a bit more to it than that …

David Hobbs’ career began with the Jaguar XK140 Drophead Coupé which was his father’s road car which had been fitted with the “Hobbs Automatic Transmission” – a transmission designed by his father who was a gifted engineer. Hobbs had already raced a Morris Oxford which had also been fitted with the Hobbs Transmission but had his heart set on racing his father’s Jaguar – although, in Hobbs’ own words, .. I can’t say it was a particularly mutual feeling between father and I …“! He did race his father’s XK140 at the Oulton Park Spring Meeting in 1960 where he managed to turn it over on the last lap! Much to David’s chagrin, many people still remember that incident and associate it with their memories of him. David survived unscathed although there was some damage to his dad’s car – which I imagine didn’t go down too well …

David Hobbs’ Jaguar XK140 which was rebodied after its accident by Freddie Owen and sprinted by Owen and Dick Tindell

To make matters worse, when David drove the rather battle-worn car home that day, the bonnet flew open and inflicted further damage to the car destroying what was left of the windscreen. David recounts, ” … after that, Dad was a bit upset and said – well, you shagged it you may as well fix it!”. Hobbs had the car rebuilt and painted in a matt finish. He had, by now, joined Jaguar as an apprentice and so had the contacts and wherewithall to uprate it for racing – starting with some decent racing tyres. He reported that he “borrowed” some disc brakes and, .. borrowed a couple of other things … and ultimately that car was quite quick”.

He said, I ended up with the ‘gold-top’ head with triple carburettor set-up and had some decent wire wheels. I put some anti-tramp rods on the back-axle, took all the interior out (or what was left of it) and got its weight down a bit”. Hobbs goes on to say, I raced like that in 1960 and ended up with four wins of one sort or another. One was a handicap race at Goodwood and other wins at Oulton and Silverstone.”  David had his heart set on the Clubman’s Championship at Silverstone which would give him the chance to drive the big circuit.

In 1961 Hobbs raced a Lotus Elite and he recalls that although I was still working as an apprentice at Jaguar, I took a lot of time off to race much to the disgust of my Supervisor“. He nearly got to drive a Jaguar again at the end of 1961 because he had a call from Mr England who asked if I would like to go to Oulton Park to drive John Coomb’s E-Type. So I rushed up to Oulton and, with a typical Hobbs piece of luck, of all people, Jack Sear’s Ferrari fell off the trailer whilst getting ready for the same race which was a support race for the Grand Prix. So Jack Sears ended up driving the E-Type instead of me – being a close friend of John Coombs and all. They let me drive in practice a bit which went very well – I was very impressed with it.”

David says“Shortly after that I tested at Silverstone with Mike Parr  and Mike McDowell who was Competition Manager at Jaguar then. I tested Cunningham’s E-Type. Cunningham had a rather special E-Type with a flared tail like a D-Type. It was one of his Le Mans cars. Parr tested it and I tested it. That was really the first time I had driven a powerful car. I had a lurid slide going through Abbey. I slid this car from just past the apex – a great long slide with all four wheels locked – ending up at the feet of Mike Parr and Mike McDowell”. Hobbs grinned and said, “Good Afternoon gentlemen.” Unfortunately, Hobbs’ slide flat-spotted all four tyres and they didn’t have any spares. The car was loaded onto a trailer and took it back to Coventry. That was the first time David Hobbs had driven a Jaguar other than a 140 – not the best of starts!

Hobbs married at the end of 1961 and left Jaguar because his apprenticeship had finished. He says, Lofty England put in a good word for me with Peter Berry and I drove his E-Type in 1962 as well as his 3.8 saloon. I drove the saloon in the British Saloon Car Championship as well as a number of GT races”. David goes on to say that Pete Berry’s cars were never the best – “always a day late and a dollar short. We were always a couple of steps behind the competition. The Ferrari GTOs were around then. There’s no doubt about it – the Coombs car and Tommy Sopwith’s car were quicker vehicles and I didn’t have any success in Peter Berry’s car. In fact, in about June he gave up racing and took up flying instead. So that was a bit of a short season!”. 

David remembers his first race in 1962 with Pete Berry’s E-Type as follows:

Our first race was the inaugral Daytona 3-hour. The fore-runner of the 24-hour … That was interesting –  I had never been to America before (certainly places like Daytona were real ‘red-neck’ country)…. Jimmy Clark was there racing for Colin Chapman. Chapman rang up and asked if Clark could drive my Lotus Elise in the same race because it was about the best that was going at the time. So Jimmy and I shared a room – he drove my Elise and I drove Pete Berry’s E-Type … he did very well but I only managed five laps before the fuel pump packed up. Jimmy was leading the class by a minute, minute-and-a-half. He came in for a pit-stop and the bloody thing wouldn’t start. After that, he and I both tested a Ford Galaxy for the Daytona 500.” Hobbs laughs and modestly says that Peter Berry had really built him up – saying he was Saloon Car Champion and all sorts of incredible stories – all of which they took in. We both tested for a Galaxy run by Holman & Moody. We both went quite quick and both turned in laps of about 155 which, at that stage, was the fastest I had ever been in a straight line let alone around a racetrack!”Hobbs recalls, Pole that year was ‘Fireball Roberts’ in a Pontiac at 159. In the end they seemed to have decided that us two limeys weren’t big enough or strong enough to drive their stock-cars”.

Fast-Forward to 1967 and Hobbs’ Encounter with the XJ13

Hobbs competed in a variety of races in the US and the UK before he was summoned by Lofty England of Jaguar in 1967. The following transcript was taken from when Hobbs was interviewed by Philip Turner (former UK “Motor” Sports Editor). This is a previously unknown interview and is published here for the first time.

Hobbs The next time I drove a Jag was some years later … 67. Got a call from Lofty again. Would I like to come to MIRA? About 6 o’clock on Sunday morning. That was the XJ13. The original V12.

Turner Was it a surprise? Did you know about it already?

Hobbs Well I knew about it inasmuch basically they had started it before I left Jaguar in 1962. I mean the thing had been kicking around since then. In fact, when I tested in 1967, I’m not exactly sure of dates and things here, but I got a feeling it had been “under wraps” at that date for about two years. 

Turner Kept under a dust-sheet in Experimental. When I went to ….

Hobbs When they finally decided to run it, it had already been built for some time. At least a year or two and they started to build it when I left in 62. And, I think, wotsisname, Norman Dewis wanted to … but they decided that, to test it, they really outta get a racing driver. Although going round MIRA, really, was particularly tame for a racing driver of course. And we went there four or five days actually. And, the lad in charge, of course was Mike Kimberley. And now your actual Managing Director of Lotus. He was just a lad then. Old Mike. Always tapping his teeth with the end of his pencil and saying, “what is it doing going over the bumps? .. would you say it wants more in or more out?”. And it was pretty basic. I mean it had the Dunlop Racing tyres of five years previously and the old Dunlop disc brakes. Pressed steel D-Type wheels. It had E-Type front suspension – rubber-mounted – polybushes – and it had the E-Type rear suspension.

Beautiful-looking thing. And a helluva engine of course cos that was a four-cam. It really gave a lot of horsepower. It gave about 500 … 525? 

Turner About 500.

Hobbs Yeah. It gave quite a lot of horsepower. It went extremely fast. We went to MIRA about four or five times. Sir William came once .. Mr Heynes used to watch it. Then they made the decision to drive it at Silverstone so they decided to get two drivers – me and Richard Attwood, another Jaguar apprentice. So off we go to Silverstone and I can’t remember the exact times but I think we did round about a 1:36 – 1:35 – 1:36. The lap record at the time was help by Paul Hawkins in his red GT40 – about 32 or 33. So we weren’t all that far off the pace. If you consider it had these old pads, old wheels, old brakes. The suspension flexed far too much of course. And of course it had no attempt at any sort of spoilers on it. Very sleek. It was incredibly quick of course down the straights.

Richard and I gave a job list of things to do. We wanted wider tyres – we wanted modern wide wheels for a start and modern racing tyres. I think those two alone would have seen us down to the lap record. And another … I seem to remember the bias front to rear brakes was poor. It wanted a lot of, you know, a good tidying up. We reckoned it would have been quick. 

They went back to the factory and, at that time, the take-over … and that was the beginning of the decline of Jaguar Cars. Really sad. Along with the whole of Leyland. The whole place just ground down. They had no idea of the innovations – they were all just numbers-men – counters. As far as making cars that people wanted they just didn’t have a clue. 

They put it under a dust sheet and it stayed there. Until Norman Dewis took it to MIRA. He’d always been a little bit piqued that he hadn’t been allowed to drive the car in the first place. Of course he rolled it into a little ball. The one that you see now, of course, is a complete rebuild.

But the car, and there’s no doubt about it, but Jaguar were beset with the same problems – mental problems – then, as they have now. They can’t go to Le Mans unless they could guarantee winning and everybody said so. Clearly, you can never guarantee winning the race. The only way you can get close to it is to go! You can test, and test and test until you are black in the face but you really aren’t going to know just how the car is going to perform You are just going to have to go. To win the race you are going to have to go.

But I really think the car would have been an absolute wow. I mean, at Le Mans, the thing would have had it. Because the GT40 in those days was an iron-block Ford that was only giving about 300 brake horsepower. I mean, this thing gave nearly 200 horsepower more than the GT40. There’s no doubt about it, it wouldn’t have been as quick as the Mark 2s, which of course raced in ’67. But it would have been very fast and, just by updating it, cos I’m sure it had been sitting in the shop for a couple of years – just by updating it.

But they had a problem. You’ve got to use Firestone or Goodyear racing tyres for example … Dunlop weren’t making good racing tyres then … for that type of stuff … 

Turner You did 160? It’s still the record isn’t it?

Hobbs It is. Yes.

Turner Did it feel incredibly quick?

Hobbs It seemed pretty quick. Smoother. 

Turner Acceleration along the straights then braking for the bends? Braking quite hard? Or?

Hobbs Not really, no. 

Turner Was it enough to lift off?

Hobbs It was quite quick.

Turner I’ve been around at 120 but not much more and even that felt fairly fast.

Hobbs Yes – very narrow isn’t it? …. 

Turner So – what did going down the straights feel like?

Hobbs At the straight at Silverstone I would bet we were doing about 150. And, of course, lap speeds of 1:36 is very quick. I don’t know what it is, 1:36? Have to look at a lap chart. A Group C now does about 1:15 .. so … 36 is quite a lot slower.

I think, the way it went, and the way that lap record stood at the time , I think with some mods and if we sat down and made a racing car I think we would have just about cracked 1:30 – probably high 1:20s … 

Turner What was it like aerodynamically?

Hobbs Very fast but no downforce of course. No downforce at all.

Turner Was it lifting at all?

Hobbs Well it probably was but it behaved like a normal racing car of the time. But, there again, the GT40s did have some downforce. They started to have downforce. Well, that was just about the time when people were just starting to tweak downforce. It grew spoilers on the back and stuff like that. The Jaguar was as clean as a whistle. You’d have probably found if you’d put some little Lola-type front spoilers on it and one on the back it would have been absolutely quick around the circuit. To be sure. Malcolm Sayer was the stylist who designed it of course and things like that would have been an anathema to him. The clean bullet-shape was the shape that racing cars were supposed to be and he might have taken a bit of persuading to get any sort of spoiler. Which, in those days, although the word wasn’t applied, was a spoiler…. See the Lola, T70, by then had the big spoiler on the back and a little spoiler on the front…. So I’m sure a little spoiler would have given a big advantage. And they hadn’t even started …

So – it seems this Hobbs is quite a special driver?

Undoubtedly so. Hobbs’ modesty shines through in his interviews but, to find the true story of his many successes, we have to look no further than his career racing history:



INDY 500

What is David Hobbs up to Nowadays?

Hobbs provides commentary for Formula One and GP2 races (alongside Leigh Diffey and former Benetton mechanic Steve Matchett), the SCCA Valvoline runoffs, and parts of the 24 Hours of Daytona. He has also worked for CBS on its Daytona 500 coverage, working as both a color commentator and a feature/pit reporter from 1979 until 1995, and then moved to Speed in 1996 working as a color commentator and then moved to NBC Sports Network in 2013.

David Hobbs appeared in the 1983 comedy film Stroker Ace, playing a TV race announcer. Hobbs appeared in the Cars 2 movie, which premiered in June 2011, as announcer “David Hobbscap”, a 1963 Jaguar from Hobbs’ real life hometown in England.

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.

How many quad-cam V12s were built and where are they now?

XJ13 Original Quad-Cam V12

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.

XJ13 - Building the Legend
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.

XJ13 - Building the Legend
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.

XJ13 - Building the Legend
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.

XJ13 - Building the Legend
3.5 litre experimental XK engine – drawing produced to calculate compression ration.
© Copyright image – not to be reproduced without permission.
XJ13 - Building the Legend

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.

XJ13 - Building the Legend
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 …”

XJ13 - Building the Legend

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XJ13 - Building the Legend
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XJ13 - Building the Legend
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XJ13 - Building the Legend

© Copyright image – not to be reproduced without permission.

XJ13 - Building the Legend
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XJ13 - Building the Legend
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XJ13 - Building the Legend
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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.

XJ13 - Building the Legend
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.

XJ13 - Building the Legend
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?

XJ13 - Building the Legend
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:

XJ13 - Building the Legend
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.

XJ13 - Building the Legend

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)

XJ13 - Building the Legend
XJ13 - Building the Legend
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.

XJ13 - Building the Legend

XJ6/2 Original twin distributors as originally fitted to XJ6/1.
© Neville Swales.
XJ13 - Building the Legend
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.

XJ13 - Building the Legend
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XJ13 - Building the Legend
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XJ13 - Building the Legend
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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.

XJ13 - Building the Legend

1967 (original car)
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XJ13 - Building the Legend
1973 (rebuilt car)
© Copyright image – not to be reproduced without permission

The words Jaguar, Jaguar XJ13, XJ13 are used in a historical/descriptive context and in no way suggest our recreations/replicas are approved by Jaguar. It is widely known that there was only ever one Jaguar XJ13 and any others can only ever be replicas, facsimilies, tributes, recreations, toolroom copies or similar.