Here are some points of trivia found on the
hotcars.com website about filming Vanishing Point:
"While Chrysler had lent out 5 alpine-white Challengers to the production house, there are rumors that one of them was originally green, having been repainted to match the director’s vision. 4 of the Challengers were relatively similar, carrying 440 engines under the hood, but one of them bore a lesser-powered 383 cc engine and had an automatic transmission. Quite unexpectedly for a car movie, none of the cars had any special modifications, save for the heavy-duty shock absorbers that had been retrofitted on the car that was slated to jump over No Name Creek."
Think I read somewhere else that the 383 auto was the one that had cameras mounted to the hood for rear-facing interior shots.
@Challenger RTA - There are some folks that believe the black car going past Kowalski is a "loop", as it appears to be the same car that Kowalski arrived in at the garage at the beginning of the movie!