Bill Thomas Cheetah
He also prepared the 1962 409 Bel-Airs and Biscaynes for drag racing and another Chevrolet stock car for Louis Unser who won its division of the Pikes Peak International Hill Climb.
[3] In 1963 Thomas gained covert support from General Motors Performance Product Group head Vince Piggins to develop the Cheetah as a concept vehicle.
Financing for the project came from private investors, Thomas, and John Grow, a Rialto California Chevrolet dealer.
Using his racing connections, Thomas arranged for material assistance from Chevrolet for the major components - the Corvette 327 engine, Muncie transmission, and independent rear-end assemblies.
[4] Following delivery of the drivetrain components, Edmunds laid them out on the shop floor and began taking measurements.
Fiberglass Trends went on to produce their own version of the Cheetah under the name GTR, which was used for drag racing.
The design of the car was unusual in that it was front engined, but with the engine sitting so far back in the chassis that the output yoke of the transmission connected directly to the input yoke on the independent rear suspension's central differential "pumpkin" housing, basically making the driveshaft only a universal joint linking the transmission with the differential.
Consequently, this design gave a front/rear weight distribution roughly approximating a mid-engined vehicle without the cost of an expensive transaxle arrangement.
This design style resulted in a hot driver's compartment - an issue that would impact the Cheetah's performance on the track.
001 aluminum car sold to Chevrolet for evaluation and later repurchased by Thomas formed the base model for the "Super Cheetah" project.
A 4130 chrome moly steel space frame was produced for the Super Cheetah, incorporating changes suggested by Chevrolet during its evaluations at Riverside with input from Bob Bondurant, Jerry Titus, and others from June 1963 to 1964.
[9] The Cheetah was to debut at the 1963 Los Angeles Times Grand Prix but crashed in practice two days before with Don Horvath at the wheel.
The sixth car was also ordered by Alan Green Chevrolet of Burien/Seattle, Washington, and was built to racing specifications.
Its outstanding documented racing record includes 10 Federation Internationale de L’Automobile (FIA) events in 1964-65.
)[citation needed] Another major problem was due to the aforementioned mid-stream change in purpose for the vehicle; because the car was originally designed as a proof-of-concept, the chassis lacked the rigidity necessary for road racing (little triangulation was incorporated into the original design).
Adding power only aggravated the problem; under hard acceleration, the trailing arms could bow outwards, allowing the rear wheels to toe in.
Owners of the car were able to improve handling by adding gussets and triangulation to the chassis, modified (or completely re-engineered) trailing arms and disc brakes.
[5] Despite some adverse handling tendencies on road courses, few cars could catch it in a straight line due to its Thomas-built 377 cu in (6.2 L) displacement, dual air-meter, fuel-injected Chevy small-block V8 based engine.
[2] Another major factor ending the project was the rapidly evolving race car design and true mid-engined configurations represented the wave of the future.
[citation needed] Thomas, faced with these negative factors as well as a fire that destroyed his factory on 9 September 1965, made the business decision to end production of the Cheetah and move on to other projects, including collaboration on the Nickey Chevrolet Camaros.
[2] The last documented Bill Thomas produced Cheetah was ordered in the fall of 1965 and delivered in April 1966.
[citation needed] A gathering of Cheetahs was held at Road America in 2014 to celebrate the cars 50th anniversary.
[citation needed] Bob Auxier of BTM Race Cars places the number at 19 chassis and 33 bodies.
It had an A pillar from the roof to the base of the windshield, something Bill Thomas' original Cheetah race car design did not have.
[2] Since about 2010 Ruth Engineering and Racing Inc of Grafton Ohio have made an updated version called the RER Cheetah Evolution which uses contemporary running gear.
