Originally posted by Dimi
It's ok if it's loud...you have a reason: Turbo...
Actually turbos quiet down your exhaust quite a bit. A 2.5" should be plenty fine for under 10 psi boost, i would just go apexn1 turbo version. I have 2.5" piping with the N/A Apex N1 muffler and it flows fine and is very quiet.