I have just put in a sirio .27 standard in my mammoth. After breakin, i have found that running it w.o.t. causes the rubber piece that connects my muffler to the ?muffler mannifold? to release the muffler. i reconnected and put a new zip tie on and found that it blew off the muffler again.
as a by product of this experience i have found that when the muffler is disconnected its like the motor has found a whole new gear or something cause it halls ___. so i was wondering is my muffler no longer able to handle the .27? it is the stock black xtm muffler that comes w/ the truck. Can anyone recommend a muffler that would allow the engine to keep some of the awsome power i saw?

thanks in advance,

jon