Thanks Pe', here is another idea that I learned about when I first went to work at the phone company. I worked with a guy who had raced Go Carts professionaly in the 50s. He and his Dad who was his mechanic ran twin Mac 10s and at a certain rpm Frank would throw a switch that bypassed the ignition points and from that point on up the rpm band the iginition timing was only controlled by the flywheel magnets. I had never heard of that before and didn't think it would work but obviously it did. Is that a new one on you also. This thread called this to my mind because Frank was always talking about about crankcase stuffing and even changing it for certain track conditions.