I got a bit of an update here. The valves didn't leak any with fluid in the combustion chamber, so that's good. Right now we are trying my redneck cc checker ( graduated syringe and a piece of drilled Lexan) but it keeps trying to leak, so we're working on that. But! I noticed the head had this lovely here,. 010":
View attachment 1715344061
I'm guessing it was milled then? Would .010" be enough to need to have an intake milled?
