The Vanishing Point car is a 440 Six-Pack 4-speed. The Fox 1996 remake used the same motivation, but not the identical car from the original movie. The original 1971 production uses four cars, one being a 383 automatic. The 1996 movie uses a 440-6 for the close-ups and three 440-4 cars for stunts and the highway runs. Ted Stevens in Alabama provided the cars for the remake and currently owns them.
Note, in the '71 movie, it is a '69 CAMARO that plows into the bulldozers! It is obvious in the close-ups, plus the Challenger had Rallye wheels on it; the Camaro had chrome reverses on it. The Camaro was basically slingshot into the dozers at about 110 mph. The remake actually destroys a Challenger.
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A '55 Chevy truck is driven by the old desert guy who meets up with Kowalski, who takes him to the revival for gas.