The Borla Pro XS Turbo muffler does not drone, nor is it quiet. For me I'll give up a few ponies for a Mercedes sound, smooth and quiet. I wil
Do the rear cat hammer and chisel job and then look at the muffler,as I have not yet seem,what it really looks like. There are dual in and dual out mufflers available, as for the resonator, it stays. It is simply a affluent chamber to eliminate some of the nasty sounds.