They don't work worth a hoot on the street. Tires are always fighting each other around a corner and a spool puts a terrible push in the car when going around a curve. Don't even want to talk about all the excitement if you happen to be out on a night when the streets are wet!!!! A light car would only serve to compound the difficulties on the street, with a heavy car there's enough weight to overcome some of the push that the spool creates....