For curbing I was thinking you could take 3/4" plywood and cut trim it down like those guys did with the floor mats. It would be much easier to trim and bevel the edges. With a good bevel the cars would roll onto them and not push them out of the way. Then you could just paint it or even use spray on bedliner to coat the plywood.
This still only works in large areas where you have the room. Smaller carpet I think the 2x4s and plastic work well.
You know the guy that beat you at the last race? It was not because of his car, or motor, or battery, it is because he was a better driver. Now go practice so you can beat him.
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