Wheel colliders are not sticking to Ground

I'm trying to make a tiny RC car for my game, and after fighting through issues from several third party vehicle assets, i decided to build my own. I did some googling on how to use the wheel colliders, and ended up with this somewhat decent result: https://imgur.com/a/XThpEiG

But as you see in the video, i have these plastic speedtracks that the car is supposed to "slide" through at a high speed, but for some reason the car is allways trying to drive the walls up and go over the edge. i havent found out what settings on the wheel collider could be causing this. I build a collider for the car that would cover the front side of the wheels. I even tried using differend physics materials on the floor and the walls of the speedtracks, which made very little difference.

Any ideas how i can fix this?