There were actually four 440 Challenger R/Ts and one 383 Challenger R/T, which was an automatic with green interior. This one was used for some exterior shots and it pulled the 1967 Camaro up to speed so the Camaro could hit the bulldozers. As confirmed by property master
Dennis J. Parrish, all of the cars were NOT originally white. They were just painted white for the film. During the scene where Kowalski has a flat tire, you can see green paint in the dents.
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