it is an older engine. It really does run great though, good temps plenty of power and good smoke. I'm using byrons 30% race in it now after the retune from his 20% I don't know if it's everywhere on the inside. The outside is immaculate. I was just wondering about cleaning everything. Maybe I'll just wipe the top of the piston off with some alcohol and be done with it since it reallly has no effect