ahh ok i see what u r saying now but to tell u the truth there hasnt been anything i have changed the exhaust on and i have never had any problems with pistons or anything with that sort. changing the exhaust on something is the best thing u can do for a an engine due to higher flow of getting rid of burned fuel. air intake, bad plugs, wrong plugs or chipping it will burn pistons letting burned fuel out better will not hurt ur pistons but help them live longer. dumping more fuel or air in an engine will burn pistons and jugs. look at it this way a engine is a air sealed bomb every bomb has its limits before exploding wrong either before or to late when u want it to, to much of something will change all effects a engine is the same thing its a bomb.but if everything stays the same and u add a better flow the better the blast and the more it does, the only real problem i see with this exhaust and even the m4 exhaust is i am wondering what they r doing with the 3 way catalytic converter system that the OEM exhaust has and was wondering if it will still pass emission laws and not turn on the check engine light.
nate
nate