By the time Carroll Shelby’s Cobra started embarrassing Corvettes on road courses and drag strips in 1962, the pressure inside General Motors had become difficult to ignore. Chevrolet’s flagship sports car was losing races to a lightweight, Ford-powered roadster built by a small operation in California, and the people responsible for GM’s performance image knew something had to change. The problem was that GM was bound by the auto industry’s self-imposed racing ban, which meant any response would have to come through channels that didn’t officially exist.
That’s where Bill Thomas came in. Born in May of 1921 and based in Anaheim, California, Thomas had spent years tuning and preparing Chevrolet products for competition. He began his career preparing Corvettes for racing in the mid-1950s, eventually opening Bill Thomas Race Cars in 1960. By the time the Cobra problem surfaced, Thomas had built enough credibility with GM’s performance division that Vince Piggins, head of Chevrolet’s Performance Product Group, was willing to work with him quietly. Piggins sent Thomas back to Anaheim with a purchase order for the 100 cars then required by SCCA in production classes, along with assurances of C2 Corvette parts support and less than one year to deliver a small fleet of Cheetahs.
The Men Behind the Machine
Thomas was the driving force, but the Cheetah was as much Don Edmunds’ creation as anyone else’s. The car was designed by Thomas and Edmunds, his lead fabricator, with Edmunds credited with the bulk of the construction. Edmunds was not a trained engineer working off formal blueprints. His trademark design methodology was to sketch what he thought the car ought to look like, then build it. The bulk of the initial drawings showed each major component in block form with major dimensions marked. It was a lean operation from the start. Financing for the project came from private investors, Thomas himself, and John Grow, a Rialto, California Chevrolet dealer, who owned the prototype car.
The Team That Built It by Hand
The shop at 510 E. Julianna Street in Anaheim was not a factory in any conventional sense. It was a small race car operation that happened to be attempting something ambitious: building a car from scratch around a Corvette drivetrain, with the goal of beating one of the most competitive sports cars in the country. Thomas had worked with Chevrolet engineering on a wide range of projects over the years, including racing Corvairs, high-performance Chevy IIs, and drag-racing 409s. That background gave him access to parts and people that a less-connected builder would never have had. For the Cheetah specifically, Thomas arranged material assistance from Chevrolet for the major components: the Corvette 327 engine, Muncie transmission, and independent rear-end assemblies. Other components came from the broader GM parts bin, including Chevrolet passenger car spindles and NASCAR-spec drum brakes.
Engineering the Cheetah
The Cheetah’s layout was unusual for an American car in 1963. Thomas employed a front-mid engine layout and a chrome-moly tubular chassis with independent suspension borrowed from the Corvette. The goal was weight distribution, and the solution was extreme: push the engine as far back in the frame as possible. To achieve ideal weight distribution, Thomas pushed the V8 so far back in the frame that the “driveshaft” consisted of little more than a flanged U-joint coupling. The result was a car with a 90-inch wheelbase and a roofline sitting just 42 inches off the ground, with the driver positioned almost directly over the rear axle. Entry and exit was through gull-wing doors. Rolling weight on the race models came in around 1,520 pounds, considerably less than the Cobra it was built to challenge.
The body presented its own challenges. After California Metal Shaping built the first two prototypes in aluminum, the production models used fiberglass bodies. The shape was dictated almost entirely by what was underneath it: a long nose to cover the setback engine, a minimal rear, and a cabin that left very little room for anything other than the driver. Aerodynamic issues and a flexible chassis didn’t do the handling many favors, and the extreme rearward seating disconcerted some drivers. The car was also genuinely difficult to be inside at speed. The exhaust headers ran above the driver’s legs, and the heat inside the cockpit at racing speeds was severe enough that at least one driver had the roof cut off his car just to make it bearable.
The Corvette V8 at Its Core
The chromoly space frame was designed by Don Edmunds to make use of the extensive Corvette race car parts bin. The car ran using a Chevrolet 327ci engine with the Muncie gearbox attached directly to the rear differential via universal joint. Different cars received different engine configurations depending on their intended use. Some cars were equipped with a fuel-injected 327ci Chevrolet Corvette engine. Others received a 377 cubic-inch small-block built by modifying the Corvette’s 327, with output estimates ranging up to 485 horsepower in some configurations. The prototype was sent to the GM Proving Grounds, where it impressed Zora Duntov. On a straight, the Cheetah was fast. The car hit 185 mph at the 1964 Road America event at Elkhart Lake and reportedly reached 215 mph at Daytona that same year. Those numbers put it in serious company.
Racing, Fire, and the End of a Dream
The Cheetah’s competition debut was not clean. The car was set to debut at the 1963 Los Angeles Times Grand Prix but crashed in practice two days before with Don Horvath at the wheel. Its first official event came on February 1, 1964, at the Cal-Club event at Riverside International Raceway, where it crashed at the end of the first lap. A water hose had come off, spraying water under the rear wheels. Jerry Titus, a journalist for Sports Car Graphic who also drove the factory car, became one of the Cheetah’s most visible advocates in print. His coverage helped sustain interest in the project during a period when its track results were inconsistent at best. The car won a number of races in 1964 in the hands of capable drivers, though it suffered from the problems typical of any new racing project. The most successful Cheetah campaigner was Ralph Salyer, who owned and drove what became known as the Cro-Sal Cheetah, named for his mechanic Gene Crowe, winning 11 minor events between 1964 and 1965.
When the Fires Came
The Cheetah program was already under pressure before the fire. In 1964, race car homologation rules changed from 100 cars to 1,000 cars, which prompted Chevrolet to advise Thomas that they would no longer support the Cheetah project. Another major factor was the rapidly evolving race car landscape: true mid-engine configurations were becoming the standard, and even the Shelby Daytona coupe was being rendered obsolete by the Ford GT40. Without Chevrolet’s parts supply and with no path to the homologation numbers needed to compete in the classes the car was built for, the program had no clear future. Then, on September 9, 1965, a fire destroyed Thomas’ factory. It wiped out cars, spare parts, and the wooden body bucks used to form the fiberglass bodywork…