This is a great foundation of a game with an incredible feat of achievement for adding in a multiplayer mode as well!
The driving mechanics felt nice and in control, however I didn't quite like the turning; mainly due to the camera. I imagine you have a lerp function in which the camera pans out as speed increases and pans in as speed decreases. I suggest expanding it slightly so that this lerp won't in effect during the turns so that the camera stays in place during a turn. Of course the slow down for turning need to tweak to not make the car slow down as much causing the camera to "snap" close when no longer turning.
Well done mate!