I'm trying to find a way to get a little more power out of a .18 engine that isn't practical to upgrade, and I remembered reading an article about porting and polishing nitro engines, so I dug out the article and grabbed some worn-out parts to practice on. Pictures follow; before is on the left, after is on the right.
Conrod beveling and polishing
Cylinder sleeve porting and polishing
I dug a little too deep on one of the guide channels and changed the shape of the inner port surface, but that's what practicing is for. Anyway, the alteration is on the lower edge of the port, so it shouldn't affect timing even if I were going to use this cylinder sleeve again.
Comments? Suggestions?