Thanks for all the input. I will do a compression check and see what I get. Use that link and do the calculator. The heads are the 84cc ones. The best gasoline here is 91 octane with 10% ethanol. I don't know if the engine builder verified the 10.25 but it is likely. Although the carb is not completely dialed in, per the A/F meter it isn't going lean at full throttle. The engine builder has the same engine in a Charger with a wilder cam and much steeper gears and torque converter. I don't think I would want to go to a much wilder cam. I would rather try a thicker head gasket or shave some off the tops of the pistons. I drive the car on long trips and around town. The power before the ping sets in is nice, but I want to feel what it is really capable of.