Ok, So it looks like I'm going to take some advice I've seen here and put on a flowmaster 40 or super 44 offroad, in place of my stock muffler on my '08 jk 4dr. Anybody know how much hp/torque gain to expect? Also, thought not my primary concern, mpg increases? And lastly, I'm not planing on relocating it, so it'll still be pretty far behind me-how loud should I expect the interior noise to be?
Last edited by Xyster; 12-04-2007 at 02:38 PM.