The car used for chase scenes was reportedly a GT fastback equipped with a 390-cu.in. V-8, while a few 289-cu.in. Mustangs were dressed to look like the 390-powered version and used for other scenes. The GT’s four-speed gearbox wouldn’t have required the double-clutching heard during the chase, but the producers opted to use an engine soundtrack from a Ford GT40 for a more dramatic effect. As for the stunt driving, McQueen piloted the car for all but a few scenes about 10-percent of the scenes, with friend and Hollywood stuntman Bud Ekins taking the wheel for the early part of filming, followed by Loren Janes for the rest of production.