Yeah I was thinking about the exhaust too and I think I'm gonna go with a 2 inch exhaust.I checked the Kameari website and seen some great stuff. B Projects Japan's Ebay store has great stuff too but are kinda expensive. I was looking at headgaskets and seen that there are different thickness. How thick should my headgasket be for my build? Also what grade of motor oil do I have to use in the US? I used SAE50 oil in my A15 B310 back home but never knew what oil they used here.