Interesting game. Love you use of 3D, it's not that often that we see that in a gamejam. I know it's a gamejam and you already know what I'm about to say and you just lacked time but : You should add a catch-up mechanic so the car behind have greater max speed. Sound design of the engine is really lacking.
Viewing post in Rush Hour jam comments
Don't worry. In a game jams, you can't do everything. So it's important that you decide before the jam what you are going to focus on. For example, my team and I, we decided to focus on UI/UX even if the game loop was very un-original. GL for doing what you could and doing a game that has a beginning and an end (we could not even do that on our 1st jam)