The Granatelli Turbocar, known also as STP-Paxton, is one of the most unusual open-wheels cars ever constructed. The car was designed by Ken Wallis as the Andy Granatelli’s STP entry in the Indianapolis 500, and was built in Andy Granatelli’s brother Joe at STP’s Paxton division in Santa Monica. The Turbocar was built around an aluminum box-shaped backbone. The driver was seated on the right side of the backbone, while the engine, a Pratt & Whitney Canada ST6B-62 turbine engine, was mounted on the left side of the backbone. The engine was based on small aircraft engine which would become one of the most popular turboprop aircraft engines in history. The engine drove a Ferguson four-wheel drive system, which transmitted the power to the wheels. A torque converter eliminated the need for a clutch pedal and gearshift. The engine idled at 54% of full throttle, which meant that the driver didn’t even have to press the accelerator pedal to pull away; all he had to do was ease his foot off the brake pedal. With the engine intake area restricted by USAC to 23.999 square inches (154.83 cm2) to limit the turbine’s power output, the engine produced 550 hp. Rufus Parnell, who raced under the name “Parnelli Jones”, qualified the Turbocar 6th with 166.289 mph. Jones qualified with a race day set-up, including the use of standard fuel (aircraft-grade kerosene),while the piston-powered entries practiced and qualified with “qualifying setups,” including light fuel loads, lightened transmission components, higher-revving gear ratios, etc. Parnelli Jones dominated the race, fighting with A.J. Foyt. Turbocar led a total of 171 laps, when on lap 196, still in the lead, just four laps to go, a transmission bearing failed, and the Turbine quietly coasted to a stop near the entrance to pit lane. A. J. Foyt drove by into first place and won the race. Parnelli Jones was classified 6th.
|1967||USAC National Championship||Indianapolis 500|
|Parnelli Jones||40||STP Division of Stubebaker Corp.|
|Granatelli||Turbine 4||STP Oil Treatment|