The 1953 Cunningham C-5R is powered by a 331.1 cubic-inch Chrysler eight-cylinder, hemi-head engine with Zenith downdraft carburetors developing 310 horsepower at 5200 rpm. It sits on a 100-inch wheelbase and weighs 5200 pounds.
The C-5R was developed for the 1953 LeMans with Phil Walters and Briggs Cunningham using LeMans statistics for the past decade to carefully determine what would be required to win. A solid front axle was chosen after Kurtis' Indianapolis cars demonstrated how sophisticated that set-up could be made and it saved 30 pounds over previous components. The power cam from the Chrysler Hemi would increase speed and the lighter weight would allow the 17-inch Alfin drum brakes to slow the vehicle quicker.
The C-5R recorded the fastest kilometer at Le Mans in 1953 - 154.81 mph Driven by John Fitch and Phil Walters, the car average 104.14 for the 24 hours, nearly 8 mph faster than the 300 SL's winning average in 1952. Alas, a Jaguar was nearly 9 mph faster than the 1952 winner. What no one had counted on in 1953 was the British team's new Dunlop disc brakes. The C-Types out-braked everybody in the field, finishing 1st, 2nd, and 4th. The Cunningham C-5R, in 3rd, prevented a clean sweep. The first Ferrari to finish was 5th; Alfa had retired. After LeMans, Briggs dispatched Phil Walters to England to buy disc brakes for his team.
In the 1950's Briggs began focusing on the 24 Hours of Le Mans, a grueling and very prestigious race. The way he wanted to conquer this race was with a formula that had never been done before - using an all-American racing team. American drivers and American cars had won races in Europe before, but the combination of American car and American driver had never been successful at Le Mans.
Unfortunately, Briggs was never able to ascertain this goal, but he and his racing team did accumulate many successful finishes at Sebring, Elkhart Lake, Bridgehampton and more.
For the 1950 Le Mans, two Cadillac's were prepared for the race. The first Cadillac was custom built and dubbed 'Le Monstre' by the French. This car was very large and not very visually appealing. It was built in the 'off-hours' by a group of engineers from
Grumman Aircraft. The other Cadillac that was entered was basically a stock Coupe de Ville with minor modifications. To finish the race is considered a major accomplishment; the duo finished 10th and 11th.
His best finish at the race was a 3rd place finish in 1953 and 1954. In 1952 he managed a fourth place finished and in 1954 a 5th place finish.
The Le Mans had homologation rules meaning that a certain number of street versions of vehicles being raced needed to be produced. Cunningham satisfied this requirement by producing vehicle out of a factory located in West Palm Beach, Florida. The vehicles were expensive; $9,000 for the coupe and $10,000 for the roadster. In turn, less than 30 vehicles were purchased and produced soon ended.
To prepare for the 1951 Le Mans, a prototype was built and designated the name 'C-1'. This vehicle featured a Cadillac engine but the relationship between Cunningham and Cadillac did not last due to insufficient financial support on behalf of Cadillac.
Cunningham approached Chrysler who in-turn gave him their full support. Cunningham was able to purchase the Chrysler engines at a 40 percent discount.
A second prototype, the C-2R, was developed using a Chrysler built Hemi engine that was capable of producing 180 hp stock. The compression was modified from 7.5 to 8.6, four downdraft Zenith carburetors were fitted and the result was a 220 horsepower. After additional testing and modifications, exhaust and intake porting, the output was further increased to 270.
The chassis for the C-1 and the C-2R were identical. They featured Cadillac drum brakes, Chrysler's worm-and-sector steering, and Oriflow shock absorbers provided by Chrysler. The C-2R had a top speed of around 152.
The vehicles Cunningham built were very fast but they were also very heavy. The drum brakes were large, but the weight and the speed of the vehicle were some times too much. A combination he was never able to perfect.
In 1952, the C-45 and C-4RK coupe came into existence. They were lighter and smaller than the previous designs. Horsepower output had been increased to 325. Cunningham entered the Le Mans with three cars and six drivers. Two car were unable to finish and were retired from the race. The other car Briggs drove for nearly 20 hours. Bill Spears finished the final four hours. They finished the race in a very impressive fourth place.
In the 1953 Le Mans race, the C-4R finished seventh and C-4RK finished tenth. The C-5R finished third being only forty-two miles behind the second place vehicle. The first place vehicles were Jaguars fitted with disc brakes. If the Cunningham vehicles had been outfitted with disc brakes as well, the race may have finished differently.
In 1954, the two C-4Rs produced a third and fifth place finish.
The C-5R featured a narrow tube frame and an aluminum body. By using a straight-axle, torsion-bar, front suspension, thirty pounds was able to be shaved from the weight of the vehicle. The rear of the vehicle featured a live rear axle with torsion bar suspension.
During a 12-hour endurance race in Reims, the C-5R and driver, John Fitch, endured a wreck that caused the vehicle to go end-over-end. Fitch survived and the vehicle was returned to the U.S. and rebuilt.By Daniel Vaughan | Mar 2006