Soo, I made the car more believable. It has working brake lights (WOOW), and new engine sounds that make it sound more powerful, but also added something extra spice, like exhaust backfire, that is programically made, with a multitude of firecracker sounds that I then processed. Besides that I also added a turbo blow off sound. They use the simulated rpm to decide their pitch and intensity, while also considering the throttle difference and position.

Last thing (visible in the last seconds of the last video), I improved the crash physics with detachable parts and deformable chassis.