RE: Engine timing..
Well I already have plans to do some back to back testing after each change. i'll start out with cleaning up the ports and radius the bottom edges. I am thinking of playing with head shims, Nitro, and plug ranges too see the difference with that. Also have the Jett Stream muffler to add into the mix. Maybe clean up the carb/ crank entry, and raise the exhaust timing is about as far as I know to do.
Filling the crankcase could be an option. Not sure what to use and or where to put it.