VERY NOT TRUE.
I just took the 30 round the block to straighten out the camber after jacking the front wheels up.
Got up to 60 in 3rd gear and flicked the ignition off, rolled for a while and turned it back on and FARKIN BANG, sounded like a shotgun goin off in the backseat. (dad could hear it and i was a bout a kay away from home). Thought the exhaust note sounded different so i pulled over and from one keybanger theres a hole in my mullfer big enough to put a fist thru. Sounds pretty good thou. so if
Some advice: If you don't wanna blow your muffler, don't DO THEM to begin with haha.