I am building a 12th scale oval car for a tight paperclip track, (70 ft runline! )Is rear steer a good idea for the car or would it make it too unstable?

It couldn't hurt to try it. It works for the 10th scale cars

The guys at our track went back to no rear steer ,we are running a 88 ft run line, yes it works on the 1/10 cars but 1/12 didn't seem to like it .