In the opening scene Fox is racing a yellow 1969 HT Holden Monaro. When the HT crashes over the VW it changes into a 1968 HK Holden Monaro. Note tail lights.
In the first drag race of the movie Fox is racing a yellow Holden Monaro. During the burnout the Monaro sounds like a V8. When the Monaro crashes, the hood flies off and a 6 cylinder engine is clearly visible.