I have a 400 with 2.5" lbm's from RARE with a 2.5" dual magnaflow kit with 14" mufflers and x pipe coming out behind the rear wheels in the stock location.I had to have the muffler shop make a head pipe to mate to the manifold because the magnaflow kit was for headers. I personally think it's one of the best exhausts I've heard on a bird. Not too loud, but a nice roar when you get on it and a nice growl at 2000-2500 rpm on the highway. A lot quieter than flowmasters or pypes, so if you want it loud, might not be for you.