I want to upgrade my pistons, but still want to keep my car smog legal? I was wondering what upgrade pistons would help me gain power but still pass smog. I was thinking about the Type S, but I don't know if I can pass smog with those.

 

as for the visual, any pistons will pass...as for emissions, type s wont be a problem at all, as for others, i dont really know too much about what high comp pistons effects are on emissions

 

Do you know what is involved in swapping out pistons? Its not the most straight forward job in the world. You might have to rehone the cylinders for proper ring seal. Go for a bolt on, and start your way up.

As for smog, I dont think it'll make a difference. Cams on the other hand will...