Bill Thomas Cheetah

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Bill Thomas Cheetah

The Bill Thomas Cheetah was a street/race car built in the early to mid-1960s by well known Chevrolet performance tuner Bill Thomas as a competitor to Carroll Shelby's Cobra. The prototype was largely designed and built by Don Edmunds, an employee of Thomas' although Thomas was closely involved coordinating support for the project. Using his racing connections, Thomas arranged for material assistance from Chevrolet for major component parts - specifically, the engine, transmission and rearend. The original concept behind the car was that it was to be a styling exercise to show GM what Thomas' company was capable of doing. Eventually, Thomas decided the car would also compete on the racetrack.

California Metal Shapers formed the first coupe body from aluminum. Once the rough body arrived back at Thomas' shop, it was finished by Don Borth and Don Edmunds. A second car was constructed with an aluminum body but the remainder were fiberglass. The chassis was constructed of Drawn Over Mandrel (DOM) cro-moly tubing that was arc-welded. The design of the car was unusual in that it was front engined, but the engine sat so far back in the chassis that the output yoke of the transmission connected directly to the input yoke on the differential without an intervening driveshaft. This gave a front/rear weight distribution roughly approximating a mid-engined vehicle without the cost of an expensive transaxle arrangement. Financing for the project came from private investors including Thomas himself and a Rialto, California Chevrolet dealer, John Grow.

The racing history of the Cheetah is not particularly noteworthy in that the car suffered from the numerous teething problems that would plague any new project. Ralph Salyer owned and drove the most successful racing Cheetah, in which he won several minor events. His car was known as the Cro-Sal Cheetah, named for its mechanic Gene Crowe and Salyer. It is also became the most recognizable Cheetah after Crowe cut the roof off to keep Salyer from suffering heat exhaustion due to his close proximity to the engine. The result was the only known Cheetah roadster.

The car was prone to overheating, due in no small part to the failure to account for vents to draw hot air out of the engine compartment. Eventually, the overheating problems were solved by using a larger Pontiac NASCAR radiator and by cutting various configurations of holes in the hood and full-length belly pan and adding spoilers to draw the hot air out from underneath the hood. Another problem was due to the aforementioned mid-stream change in purpose for the vehicle; the chassis lacked rigidity, thus it was a challenge to carve predictable curves through turns on a track. Adding power only aggravated the problem as the trailing arms (in their original configuration) were flexible, allowing the rear wheels to toe in under acceleration. In short, getting the vehicle to launch out of the corners without scaring oneself was almost impossible. However, once the vehicle was lined up on the straights, few cars could catch it due to its Thomas-built 377 cubic-inch, dual air-meter, fuel-injected engine. On the dragstrip, the car reportedly posted faster numbers than the much vaunted 427 Cobra.

A fire in the factory destroyed the original plywood body buck, the factory drag car and some spare parts inventory and thus contributed to the demise of the car. The other major factor in the end of production was the adherence of General Motors to the automaker racing ban, thus killing backdoor projects like the Cheetah and the much required parts supply. When the parts supply dried up, there was no way for Thomas to achieve the homologation numbers needed for racing, which went from 100 to 1000 units. The remaining cars were left as highly desirable collector items. No official records are known to exist documenting the exact number of cars produced, but best estimates indicate 23 cars were built to varying degrees of completion.