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Jaguar D-Type


Jaguar D-Type at LeMans 1955
Over the winter, Jaguar built new D-Types for the 1955 season. While the basic design was the same, there were important improvements and refinements.

Whereas the 1954 car's central tub and forward space frame had been integral, the two elements were now separate and attached by bolts. This was mainly to make crash repair easier. To make manufacture easier, the front frame was made out of steel tubes, which could be bronze-welded together by journeymen, rather than the argon-arc specialists the aluminum had required. Yet the steel frame was lighter.

The Jaguar D-type at LeMans in 1955.
©2007 Jaguar Cars and Wieck Media Services, Inc.
After falling short at LeMans in 1954, the Jaguar
D-Type came back in 1955 with more power and
a new nose for improved aerodynamics.

Engine power was up, thanks to a new cylinder-head casting. Both inlet and exhaust valves were now larger, and to get the latter to fit, exhaust-valve angle had to be changed from 35 to 40 degrees from the vertical. The inlet angle remained 35, so the included angle was now 75 degrees, but these were forever known as the "35/40 heads."

Camshaft lift was up an additional 1/16 inch, and cam timing was yet another stage more radical. With retuned intake and exhaust manifolding, output was now 270 horsepower over a nice, broad spread of 5,500-6,000 rpm. To help nail this down out of slow corners, Jaguar installed ZF limited-slip differentials for the first time.

On the outside, the 1955 factory team car looked a little leaner and meaner because the radiator inlet was brought forward 7.5 inches, the better to pierce the air. Brake cooling inlets were added, too. The driver's windshield got more of a wraparound, and the fin was extended more toward the tail.

Frontal area was up slightly, to 12.8 square feet, but other body refinements combined to lessen drag a further 16 percent (to 32 horsepower at 100 mph) and permitted a slight easing in the front-heaviness (to 52.5/47.5 percent) without any change in the at-speed values.

Hindsight is of no more value in racing than in any other part of life, but it would have been better had Jaguar never gone to LeMans in 1955. A tragic foreshadowing of what was to come occurred when William Lyons' only son, John, was killed in a head-on crash with an American army truck on his way to the track.

At LeMans for its second year, the D-Type Jaguar faced not only Ferrari with its all-new, 4.5-liter six-cylinder cars, but Mercedes-Benz, back in the sports-car fray with a two-seat, 3.0-liter version of its fuel-injected, straight-eight Formula One car. Aston Martin and, this year, Maserati were contenders, too.

During the first stage of the race it was a Ferrari in front, but it faded after a while, leaving a fierce battle between the Mercedes of Juan Manuel Fangio, who had already won two of what would be five world driving championships, and Jaguar's Mike Hawthorn, a future champion in his own right.

Against the D-Type's disc brakes, the Mercedes 300SLR was deploying an air brake, a large flap behind the cockpit that the driver could hinge up into the airstream to help slow the car for corners. Germany's "silver arrow" was thus able to stay with the green British bullet on the brakes, and it showed superiority through the corners themselves.

But the Jaguar had better dig away from the turns and better top-end on the long straight. Effectively equal around the track as a whole, two of the fastest men in international racing were putting on a real Grand Prix. Inspired, Hawthorn set a lap record at an incredible 122.39 mph.

Then he came up to the pits for his first refueling stop. Trying to save time by not braking until the last instant, Hawthorn swerved right toward the pits in front of American driver Lance Macklin's Austin-Healey. The slower car veered left, into the path of a silver Mercedes coming up behind -- not Fangio's car but that of teammate Pierre Levegh.

The Mercedes launched off the Healey and flew diagonally to the left, over a low embankment into an otherwise unprotected crowd of standing spectators. More than 80 were killed in addition to Levegh. It was the worst accident in the history of motorsports.

All heart was gone from everyone, but, fearing worse confusion if they stopped the race, officials let it continue. The Jaguars lagged, and the surviving Mercedes cars droned on ahead until an executive order was telephoned from Stuttgart to pull out.

Hawthorn and co-driver Ivor Bueb soldiered on around to claim a hollow and very somber "victory," one which Jaguar refused to advertise.

For more on Jaguar and other great cars, see:

  • Jaguar Cars: Check out more information on the great sporting cars.
  • How Sports Cars Work: Get the lowdown on hundreds of fantastic sports cars from the 1940s to today.
  • Classic Cars: Learn about the world's most coveted automobiles in these illustrated profiles.
  • Ferrari: Learn about every significant Ferrari road car and racing car.
  • New Jaguars: Reviews, ratings, prices, and specifications on the current Jaguar lineup from the auto editors of Consumer Guide.
  • Used Jaguars: Reviews, recalls, trouble spots, and more on pre-owned Jaguars starting with the 1990 model year. From the auto editors of Consumer Guide.