A One-of-Two 1957 Chevrolet Corvette SS XP-64 Comes Up For Sale

 

Along with perhaps the Ford Mustang (although technically a Muscle Car) and the Shelby Cobra, the Corvette is probably the most prolific American sports car ever to be put on the road. The reason for the Corvette’s creation lies in the fact that soldiers returning from Europe after WWII, were bringing over compact European sports cars from the likes of MG, Healey, Alfa Romeo and so on. GM’s Head of Styling Section, Harley Earl, recognized the commercial potential and green-lit the construction of a compact 2-seater under the codename Project Opel (After carmaker Opel, owned by GM at the time) at some point in the early 1950s. The result was the EX-122 prototype, which made its public debut at the 1953 General Motors Motorama in New York and entered production later that same year.

Built in 1957, the Corvette SS XP-64 was Duntov’s vision and personal project of what a proper racing Corvette. The car had been used in racing before, but primarily in production-based stock car form.  A year before the SS XP-64 would hit the track, Duntov campaigned and drove a series of stock and lightly modified Corvettes throughout 1956, proving the car’s capabilities in pretty much every race it entered. The SS XP-64 however, would turn things on their head, as it was the first purpose-built GM racecar, made possible by Duntov, Cole and Earl. GM’s intentions were to take the car to Le Mans, and use other races as proving ground and shakedown events in preparation for the legendary endurance race in France. A Mercedes-Benz 300 SL was sourced to use as a starting point for the chassis, but eventually, a lightweight custom tubular chrome-molybdenum frame was built by Duntov’s and Earl’s team.

Power came from a 283 cubic-inch (4.6-litre) Chevrolet small block V8 fitted with high-performance parts that would up the power and lower the weight. A number of experimental components were used, such as an aluminium water pump, radiator core and clutch housing, as well as a magnesium oil pan. It was also fitted with Chevrolet’s Ramjet fuel injection system, comparable to top European race cars at the time. The engine’s output was about 310bhp, which was fed through a four-speed close-ration gearbox and breathed through side-exit exhausts.

Both cars were brought to Sebring for the 1957 edition of the 12 Hours, with John Fitch and Piero Taruffi replacing Stirling Moss and Juan Manuel Fangio who initially signed up to drive it. Running the fibreglass car first, the duo clocked in reasonable times in practice. With Duntov insisting on driving the magnesium car as well, lap times dropped considerably! During the early stages of the race, overheating issues caused technical problems with the car, forcing it to retire after just 23 laps (out of what ended up as a 197-lap race for the winner, Juan Manual Fangio in a Maserati 450S). Shortly thereafter, the Automobile Manufacturers Association voted to ban all racing programs for its member companies, which included General Motors and thus Chevrolet. That rendered the promising Corvette SS XP-64 obsolete, and it never raced again.