Great racing cars: 1991 Jaguar XJR-14



A series taken from the 164-page Motor Sport special Great Racing Carswhich is available to buy here.

From the editor Damien Smith

How would you define a ‘great’ racing car? Race wins and championship titles are an obvious place to start – and admittedly, when we began the process of rounding up the ‘voices’ to fill this special magazine, published by the team behind Motor Sport, we had in mind the likes of the Lotus 72, Ferrari F2004, Porsche 917, Audi R10 and so on.

But as the interviews of familiar racing figures began, we realised greatness is often a very personal thing. Naturally, most – but not all – would pick cars they had experienced first-hand, as a driver, designer, engineer or team boss. And on occasion the cars that stood out in their minds as ‘great’ weren’t necessarily so in the grand scheme of history. That’s why you’ll find a Minardi here among Formula 1 cars from Lotus, Williams and McLaren.

Unexpected? Certainly. Wrong? Not to the man who chose it.

As the interviews accumulated, our magazine took on a life of its own, full of personal anecdotes about the myriad cars that made careers. Some of those we spoke to, such as Mario Andretti and Dan Gurney, couldn’t be tied to a single choice from multi-faceted lives at the wheel. Such heroes have earned the right to choose an F1, sports and Indycar, so we allowed them more than one bite.

Others refused to be confined by category. Hence the short ‘Odd ’n Sods’ chapter on cars that, by and large, are mere footnotes in lower divisions of racing lore.

Thus there is nothing definitive about the selection listed herein. Then again, there’s no claim that this compilation offers the ‘Greatest Racing Cars’ of history. It’s much more personal than that, much more quirky – and all the better for it.

1991 Jaguar XJR-14

Martin Brundle
1988 World Sports Car champion, 158 F1 Grands Prix

The XJR-14 stuck to the ground, gave you confidence, did everything it was supposed to do and was an absolute pleasure to drive. I used to challenge myself in it, because you’d go through a corner with so much speed and think, ‘I can’t believe I just did that. Right, see if you can do this, then…’ It was almost a lap by lap personal challenge. It was a Ross Brawn car, basically a single-seater with bodywork, and I was involved from the get-go, having sat in a balsawood buck, choosing where I wanted the steering wheel, gearlever and all that sort of thing.

The stand-out races were probably Monza, where I finished first and second, and Silverstone, where I lost 10 minutes with a broken throttle cable but still finished on the podium. I took three laps out of Schuey and his gang with the Merc, five out of the Peugeots and two out of my own team-mates, while driving solo. I thought that was a reasonable effort.

It was a car in which I felt totally and utterly at one.

Derek Warwick
Le Mans winner, 1992 World Sports Car champion, 147 F1 GPs

I’m tempted to choose my little Hawke DL15 Formula Ford, which was a pretty incredible car, but I’m going for the Jaguar XJR-14, a pure thoroughbred, a Formula 1 car with clothes on and spectacular to drive. I tell you, that Ross Brawn car was just unbelievable, probably the best racing car I’ve ever driven.

The Jag was the first small, nimble Group C car because before that we had the Porsche 956 and 962, the big V12 Jaguars, and the XJR-14 simply moved Group C into a different era. This was a real thoroughbred racing car.

I remember the first time I sat in it, at Silverstone on the South Circuit, and I did the installation lap, came in, spoke to Ross, and said, ‘This car is just incredible’. And that was just an installation lap, it was that good, I knew immediately.

On my first flying lap, through the right kink by the makeshift pits we had at that time, there was always a dab on the brakes, or you’d come down a gear. But not with that Jaguar. It was flat in top gear… and it made me laugh, because I could see all the guys ducking down behind the barrier because they thought the throttle must have stuck open.

The ‘fat’ F1 car
The sports car that had no doors

The 3.5-litre Group C formula encouraged a new breed of sports car based around F1-spec engines, but it didn’t mandate it. The chassis rules were largely the same as for the old fuel-formula Group C machines, save a new weight limit of 750kg, down from 900kg, and a concession to allow perspex windscreens.

What wasn’t the same was the mindset of Ross Brawn and the design team he had established at Tom Walkinshaw Racing, after his recruitment from Arrows after the end of the 1989 F1 season with instructions to spend a whole year designing the car around Cosworth’s Ford HB V8.

“The starting point was the question: how keenly can we interpret the regulations?” explains Brawn. “We took a very competitive interpretation of the rulebook from a structural and aerodynamic perspective.”

Essential info: Jaguar XJR-14

Entrant: TWR Jaguar
Notable drivers: Teo Fabi, Derek Warwick, David Brabham, Davy Jones, Martin Brundle
Debut: 1991 Suzuka
Achievements: 6 wins, 11 poles (WSC & IMSA)
Constructors’ Championships: 1 (WSC: 1991)
Drivers’ Championships: 1 (WSC: 1991)

Just look at the XJR-14 in our photos, resplendent in surely the best of the Silk Cut liveries. It looks like nothing that came before it. Group C sports cars of the day had doors. The XJR-14 had windows that popped out — a mechanic was assigned to play catch at pitstops. It was central to the concept of creating what chief designer John Piper calls “a fat F1 car”.

“There was a regulation stipulating the size of the [side] window and the size of the door,” he explains. “We made them the same thing. That meant you didn’t require a dogleg in the tub, which meant you could have a narrow, high-sided and very stiff monocoque.”

The narrow chassis allowed the TWR technical team to move the radiators out of the nose and into the sidepods, freeing up the nose for aerodynamic gain. Here again, TWR came up with a novel interpretation of the rules to get sufficient airflow behind the front wing that distinguished the XJR-14 from its forebears.

Brawn again: “We checked the crash-test regulations and it stated that there could be no damage to the survival cell beyond the pedal line. That meant there was a large chunk of the chassis that you could damage and that allowed us to achieve the short nosebox.”

The XJR-14 chassis, produced by TWR’s in-house ASTEC composites company, didn’t quite make it through the test as planned. The damage to the monocoque was more extensive than envisaged, which meant the pedals had to be moved backwards.

That wing was crucial – though never entirely successful — in trying to balance out the massive amounts of downforce generated from the underside of the car courtesy of another bit of clever rulebook interpretation.

Piper: “The rules stated that you could have a two-element rear wing, but there was no regulation on the distance between them. So we put the second plane down level with the diffuser, which effectively gave us a massive extension.”

That explains downforce numbers that were, according to Brawn, “an order of magnitude more than were being achieved in F1 at the time”. He points out that the Jag was capable of lap times that would have qualified it on the back of an F1 grid. “You could work it out,” he says. “We were nearly 250 kilos heavier than an F1 car, and today that would equate to 10 seconds.”

Taken from the January 2013 issue of Motor Sport. To read more click here.

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