It doesn't bottom out, apparently has anti squat bars … It hits the rev limiter and bangs like m-80's going off and flames shoot out a bit... I was told its normal for the Boosted engines and more so for a 5.4 with the bigger 2013 5.8 charger on it and smaller pully .. Im thinking a straight thru muffler maybe would be better... I don't know for sure...Oh wow - do you have a way to take / attach a picture? On the Bottom....bottoming out?