I'm planning to get a b18c on my ej6 next 2 months maybe. I also want to build it before i drop in the motor. I was looking at Jun's product stage 2 cam set. piston. Bore 81.0(not sure what this means)what is bore? 81mm is the piston size i think whats the stock b18c piston size? if i put this in a b18c do i have to make the sleeves bigger? or port it or something like that. IF i get this piston kit do i also need to get the connecting rod also?