The first purpose-built GM racecar.
The only Chevrolet Corvette SS completed and campaigned by General Motors.
Raced at the 1957 Sebring 12 Hours.
Powered by a Chevrolet 283-cu.-in. V-8 with Ramjet fuel injection; backed by a four-speed manual gearbox.
A design exercise in lightweight construction and aerodynamics; the sole Corvette SS built with magnesium bodywork. The car was driven by Piero Taruffi and John Fitch and retired after 23 laps with “electrical gremlins, bad brakes, and finally, terminal rear end problems.” While the XP-64 was fast, it had reliability issues, and the magnesium body made the cabin unbearably hot. |  |
The SS Project XP-64 became the most expensive Corvette of all time when it sold at auction for $7.7m. The race car was the brainchild of Zora Arkus-Duntov, the “father of the Corvette.” The Corvette SS Project XP-64 was housed at the Indianapolis Motor Speedway Museum since 1967. |  |
Beneath the skin of the car is a lightweight tubular frame made from chrome-molybdenum tubing. The body was then crafted from magnesium and aimed to be as streamlined as possible. Power comes from a 283 cubic-inch V8 equipped with a high-performance camshaft, aluminum cylinder heads, and fuel injection, producing around 300 hp. The engine was paired to a four-speed manual transmission. The SS tipped the scales at just 1,850 pounds (839 kg) dry—nearly 1,000 pounds lighter than a production Corvette. It took five months for the XP-64 to be built and begin testing. The car changed hands in 2024 at
RM Sotheby.