The real problem is that you are trying to use the physx vehicle when the original game is literally just using the equivalent of a character capsule with very little if even any movement.
Read up on the memory limits used by the original game. It’s probably N64 or even less.
Try to get the same motion going with a regular character or, better yet, a pawn.
You should be able to play with the bounce values that physx uses and actually get pretty similar results.