I ran a 3 1/2" set up on my last car for awhile. I made a unique setup by running Dyno Max Ultra flow Bullets (the short ones like 9" long) followed by a Borla XR-1 Shootout muffler right in line. It wasn't as heavy as it sounds and the XR1 dumped at the axle. I got a ton of compliments on that setup. Had a very deep clear tone and then absolutely shrieked when under full throttle.