So I just recently determined that my mustang only has an axle back exhaust. My question is what about a catback exhaust is it that creates the extra horse power? Is it a resonator delete to allow for greater airflow? Or is it just aftermarket piping? I want to take my axle back and convert it into a cutback but there is no cat to axle piping available that I have seen except for x-pipes and h-pipes. I also intend to get this and put it on once I have the money.
MST-CY78WC Mustang ARH Long Tube Headers 1-7/8" With Catted X-Pipe 3" Stainless Steel With Coarse Thread Header Bolts GT 2011-2014 | CJ Pony Parts
So I'm just looking for some advice on where to go from here to get a completed exhaust setup and get that extra hp I should from a catback setup before the headers and x-pipe. Thanks