Looks like a ‘55 chevy bel aire coup.
Not a Bel Air! It is a post top, not a hardtop, so probably a 1955 Chevrolet 210. The models would have been a 150, 210, and the Bel Air was the top of the line. It is a 2 dr sedan, rather than a hardtop coupe, naturally the post top isn’t as rare or as desirable. He definitely didn’t have proper safety harnesses, as a long time drag racer, there is no way he should have come loose like that if he had an anti-submarine belt (the one that comes from the floor between your legs. The belt broke, or wasn’t properly fastened to the frame.