Stop a car fast & safe

Is this gonna be an actual product? Would require re-setting the bumpers each heat though, I imagine?

Or maybe the "Bump Stop."

You want to keep the weight below 5 oz so the car has some travel, stopping in about an inch or two to stay below any nose damage. Also the lower weights are bars that keep the sled aligned to the stop track and let the car stop without jumping to the side. Pick a foam with a very low COR.
I am working on a composite that might be better, but use old cars to experiment with, many foams will bounce your car off to the side and bang the wheels.

All better solutions, but this is for those with no room for longer stop section or for the typical Cub race where the stop sections are sometimes demolition derby. You can take a set of these and save the day for your car, and anyone else that wants to try it. I have been to races where the stop section was three young kids slapping the cars down just before the hit they board on the end.