Jan 17 2017

Helck Family Collection: Bill Mitchell’s XP-700 Corvette Concept Car and XP-87 Stingray Racer

Another treasure has been discovered in the Helck Family Collection- A 1960 letter from Bill Mitchell, then head of General Motors Styling, to Peter Helck with photos of "my Stingray and Corvette." The two automobiles were the historic 1958 XP-700 Corvette Concept Car and the 1959 XP-87 Stingray Racer.


Howard Kroplick


A Profile of Bill Mitchell

William L. Mitchell was only the second person to hold the position of vice president in charge of General Motors Styling Section (currently GM Design Staff). He retired from GM in July 1977, capping a 42-year career, nearly 20 of them as vice president.

1958 XP-700 Corvette Concept Car

1958 Chevrolet XP-700 Corvette Concept

From the GM Heritage Center
Written by Bill Bowman 

The XP-700 was developed as a personal car for Bill Mitchell, head of GM Styling. The car started out as a 1958 stock Corvette. The fiberglass body was extensively redesigned with a "Grand Prix" appearance. The long, low front overhang, large air scoops, and wire wheels with racing hubs were a few of the "Grand Prix" touches. The XP-700 was painted red and was Mitchell’s personal ride for the first year of its life. 

By 1959, the XP-700 was modified with a longer and smaller oval grille, extended tail and double bubble plastic canopy, coated with vaporized aluminum to help block the suns rays, complete with periscope type rear view mirror. It was repainted metallic silver and was elevated to show car status. 

The sculptured deck rear end treatment found its way to the 1961 Corvette. Other features included Lucas "Flame Thrower" headlamps, Dayton wire wheels, integrated front brake cooling ducts below the headlights, forward slanting vertical louvers at the front of the scoops on the body side coves, twin outlet side exhaust pipes and ribbed mufflers, rear brake cooling ducts and a special hood.

The XP-700 was powered with a Chevrolet 283 CID 230 Horsepower V8 engine with a manual 4-speed transmission 

According to Mark Jordan, son of GM designer Charles M. Jordan, the XP-755 (Mako Shark) was built on the XP-700 chassis, explaining its disappearance.

1959 XP-87 Stingray Racer

Stingray Racer

From the GM Heritage Center
Written by Bill Bowman 
Bill Mitchell became the GM design chief as Harley Earl’s successor in 1958. He wanted to build a Corvette racecar capable of beating Europe’s best and with the availability of Zora Arkus-Duntov's defunct 1957 SS test mule chassis, Mitchell’s XP-87 was underway. Seeing as factory backed racing was taboo at the time due to an AMA (Automobile Manufacturer’s Association) ban on manufacturer-sponsored racing, Mitchell’s project had to be privately financed and the powers that be insisted that Mitchell’s design have no recognizable association with the Chevy brand or Corvette name so the XP-87 name was dropped and changed to Stingray. With Mitchell’s own time and money heavily invested into the project, he contracted stylist Larry Shinoda to assist in the development of the revolutionary concept. 
Combining the 1957 SS chassis with the new fiberglass body resulted in a sleek and muscular state of the art open roadster. Mitchell’s Stingray was completed in 1959 and with the engineering help of Duntov, was fitted with a high-compression, fuel injected 283 cubic-inch V8 engine that produced 315 horsepower and entered into SCCA C-Class competition. 

Driving duties for the Stingray were handed over to accomplished SCCA driver, Dr. Dick Thompson. Thompson raced the Stingray in any and all the races Mitchell could afford to enter, and in the end piloted the Stingray to two consecutive class championships in 1959 and 1960. At the end of the 1960 season, Mitchell retired the Stingray from competition, detuned it, added a full windshield and passenger seat, drove it on the street and exhibited it as an experimental show car. 

The Stingray’s body design strongly influenced the styling of the next generation Corvette (1963). It also was a test bed for many technical developments with a four-speed manual transmission, extensive use of aluminum and a DeDion rear suspension. 

The Stingray Racer is currently on display at the GM Heritage Center in Sterling Heights, Michigan.

The Stingray racer made an appearance in Elvis Presley's "classic" film Clambake. See mark 1:36 to 1:49 and 2:25 to 2:34.

In 2012, the Stingray Racer paid a visit to Jay Leno's Garage. See Mark 8:14 to 14:27.


Jan 24 2017 L.M.K. 10:01 AM

Very cool….I remember seeing that in Clambake and always wondered about that car…Now I know the story….Thanks Howard…

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