Hey Guys, I did the center muffler removal mod, now im over how loud it is I wanna get an xforce cat back to quiet down the car, car currently makes 278rwkw and im planning to get around 320 with my next retune. I called a few places and they are wanting aorund $700 fitted for an xforce cat back is this right ?.. Also does any know if I just put the stock middle muffler back in, will I make 320 still ?