Wow Ultratoro have a great potential!!
My suggestion to make this game even greatter:
* I'll suggest to change the music to a more "mario kart" or upbeat song, something with a clear "motiv", so the game can be remembered from its music.
* Add some effects, for example some gas particles behind the car.
* Little bounce when reaching the floor.
* Jump effect
* Synchronize the car velocity with the BG music speed.
The character controller is great, and the game is really fun to play.
Do you drive in an actual torus, or is a straight cylinder with a curved shader?