What if …

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“Jaguar XJ13” …. A name to conjure with.

… widely acclaimed as the most beautiful car ever produced by Jaguar.

… designed by Malcolm Sayer at the pinnacle of his talent.

… engineered by some of the most talented and gifted individuals of their generation.

… housed Jaguar’s first V12 engine – an engine in gestation since the 1950s.

… carried Jaguar’s dreams of a return to their glory days at Le Mans in the 1950s.  

… could have claimed laurels at the highest levels of motorsport.

… poised to compete and rise victorious over the best the world had to offer in the late 1960s.

 

It never raced, and only one was produced.

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

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.

As a lasting homage to the genius of its late designer Malcolm Sayer the car does continue to inspire with its superb lines but is likely to remain as no more than that.

However ….

We can at least examine the many contemporary records and reports that have recently come to light and can look at the XJ13 as it appeared in 1967. 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.

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 - a Le Mans winner.

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 wishbone 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 If …

What if the XJ13 had taken up a place on that 1965 grid and development had continued through to 1969 and beyond?

What if a privateer team such as the legendary Ecurie Ecosse had taken the XJ13 – as they had done successfully with the C & D-Types years before – and carried on with the car’s development?

How could history have been re-written?

What if …. ?