Make a car only drive on the road

Ok what i want to do is make my car only drive on my track which is a metal obj. I don’t want it to drive on like the ground or anything just my track.

I think the best way to do this is to use invisible walls at the edges of your track… I’d use a Blocking Volume with a brush shape of how you need it, and Physics Material to set up the friction (or lack of it)

is there a way to set up two friction types