1956 Jaguar XK-D D-Type

History

The Jaguar D-Type sports cars were produced from 1954 through 1957. These factory-built race cars were similar to the C-Type, but given more powerful engines, improved chassis, and aerodynamic bodies.
Walter Hassan was tasked with designing a sportscar for Jaguar. The result was the XK-120 which showed promise on the racing circuit. Although the alloy bodied cars were fast, it would not be a serious contender at the 24 Hours of Le Mans race. Further development was needed. In 1951 the XK 120 C, also known as the C-Type, was prepared and ready for testing at Le Mans. The straight-six cylinder engine had been modified to production 210 horsepower and various other mechanical enhancements greatly improve the performance. Three C-Types were entered in the Le Mans race with two failing to finish. The third C-Type finished strong, winning the event while averaging 93.49 miles-per-hour.

Three experimental C-Types were entered in LeMans in 1952. A long tail had been applied to the C-Type in an effort to improve aerodynamics and stability during the long, straight stretches. Unfortunately, all three failed to finish due to overheating problems. For 1953, the use of experimental bodies was scrapped in favor of the tradition bodies. The factory cars were fitted with disc brakes. In the end, this combination proved to be all that was necessary to score top finishes.

To stay ahead of the competition, Jaguar began working on a Le Mans replacement for the C-Type, resulting in six D-Types in 1954.

The D-Type was constructed of a monocoque-type chassis welded to a subframe. Later versions of the car were bolted, rather than welded, to allow easy detachment.

The same XK engine was used, albeit with minor modifications such as the use of dry-sump lubrication. The frontal area to house the engine was decreased. This was to provide for higher top speeds as Le Mans. A large fin was place behind the driver to provide stability at speeds in excess of 150 mph. Due to the new design, additional modifications to the shape and size of the engine were required to fit it into the engine bay. It was tilted 8-degrees, resulting in an off-center bump in the hood. The 1955 D-Types used asymmetrical heads, known as '35/40' heads, with intake valves positioned at 35-degress and exhaust valves at 40-degrees.

Four D-Types were entered into the 1954 Le Mans race and were not enough to beat the powerful Ferraris. 1955 modifications propelled the Jaguar marque to its third LeMans victory. A Mercedes-Benz SLR was leading the Jaguar by two laps when it was withdrawn from the race.

Though 1955 meant another victory at LeMans for Jaguar, it was a devastating year for the sport. The Mercedes-Benz SLR's were poised to capture the victory when a tragic accident occurred, involving an SLR, and killing the driver and 80 spectators. Mercedes-Benz withdrew from the race and from motorsports.

Most of the D-Types were single seaters and built for the race track. During the final year of production, Jaguar offered the Jaguar XKSS, a street version of the race car.

XKSS

Twenty-five of the 68 Jaguar D-Type race cars were left unsold when Jaguar decided to cease its participation in the International Sports Car Racing program. Jaguar decided to convert the 25 remaining vehicles into road-worthy sports cars.

The rear fin was removed, bumpers were added, and the single-seater was left topless with a canvas hood available to protect the driver from the elements. A windscreen was designed and a second door was added to accommodate passengers. With a Dual-Overhead Cam straight-six cylinder engine with 3442 cc capacity, the vehicle could race from zero to sixty in 7.3 seconds. The 250 horsepower output was capable of propelling the car to a top speed of nearly 150 miles-per-hour. Excellent stopping power was provided by the 4-wheel disc brakes.

In 1957, the XKSS was introduced at the New York Auto Show.

Sixteen private buyers purchased the XK-SS with the majority going to the United States. Two went to Canada, one to Hong Kong, one in the UK, and the rest to America. There were over 300 examples being built when a fire destroyed the machinery, assembly line, and most of the XKSS models. Steve McQueen, a film star and motor racing fan purchased one. McQueen is famous for his documentary of the 24 Hours of LeMans.

By Daniel Vaughan | Mar 2006

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Jaguar's iconic D-Type sports racing car is set for an historic return to the scene of its most famous racing victory, in a celebration of the 50th anniversary of an unparalleled 1-2-3-4-6 finish at Le Mans in 1957.

The actual winning and second placed cars from 1957 are scheduled to reappear on the track at the Sarthe circuit in June, with the kind permission of their owners Evert Louwman and Sir Anthony Bamford. It will be the first time they have been reunited at the scene since that epic domination of the world's most challenging race. They will be joined by the similar cars owned by the Jaguar Daimler Heritage Trust and Dick Skipworth.

The celebration has been painstakingly planned by Michael Quinn, grandson of Jaguar's founder Sir William Lyons, in conjunction with the Jaguar Daimler Heritage Trust.

'The 1957 victory for Jaguar was such a landmark at Le Mans that we were determined that the 50 th anniversary of it should be properly celebrated. It was, after all, a major British triumph and a great achievement for a relatively small manufacturer at the time. The Le Mans victories really helped put Jaguar firmly on the world map,' said Michael.

'Now, in 2007, the Automobile Club de l'Ouest has given its permission for the 1957
D-Types to take part in the 24 Hour trophy presentation on the start-finish straight, just before this year's race begins. Additionally they will be driven around the circuit in the Motor Racing Legends Cavalcade on Saturday morning for three victory laps.'

Jaguar had officially pulled out of racing in 1957, but were focused on adding to their success at Le Mans and so provided fully-prepared D-Types for legendary Scottish team Ecurie Ecosse, which had won the previous year, to compete on their behalf.

After a tough 24 hours that had taken a high toll on the finishers, it was the partnership of Ron Flockhart and Ivor Bueb that eventually seized victory thereby making Jaguar the most successful marque in the history of the race. It was also Ron's second successive win. Right behind were Ninian Sanderson and John Lawrence, and third place went to Jean Lucas and Jean-Marie Brussin. Belgian journalist Paul Frere and 'Freddy' Rouselle finished fourth, with Mike Hawthorn and Masten Gregory sixth.

Half a century later, 1957 remains one of the most dominant victories in the history of the classic 24-hour endurance race, and crowned a hat-trick of wins at Le Mans for Jaguar and its innovative D-Type. These wins in turn followed on from two earlier successes with the
C-Type, winning in 1951 and 1953.

It was also significant as a fitting tribute to Jaguar's tireless efforts to bring success and motor racing glory back to Britain in the 1950s, a golden era of motor sport. The Midlands-based manufacturer would not win there again until the late 1980s, the Silk Cut Jaguar
XJR-9LM taking first and fourth in 1988.

The 2007 Le Mans 24 Hour race takes place on the 8.45 miles French circuit of La Sarthe during June 16 and 17.

Source - Jaguar

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