The car is still putting down some excellent lap times on carpet with rubber tire's. We tested with the low roll center yesterday and right now the car is faster as is. Big dog and I ran the same set up's on our cars but he had the low roll center blocks on his car. Everyone has different driving stlyes so we might switch places next weekend and see if we get the same results. Have any of you guys lap times been any faster with the low roll center blocks on carpet?