I have a 3" SISO Magnaflow on the way, and plan to replace stock muffler and resonator... hopefully I can get a good 3" flow throughout, as from my research I think these 2011's have 3" pipes stock (except down to 2.5" for the resonator).
Question is, what size tip would sound good with basically a stock setup with an 18" muffler? I think there is room for a 10" tip using the stock exit, but I can prob alter the exit... thinking at least 12", with 3" in and 3.5" or 4" out. Thanks!

 

Think u are right on. 3 in 4 out, 12 inches long. I have 18 inch exiting in stock location and think I would have been fine with 12.

 

4X18 and choose either a rolled edge or slash cut

 

3.5-4" x 18"

 

Now if I could just find a black one... best bet would probably be to buy a sst one online and powdercoat or paint with a good high heat paint. Thanks...

 

Yep. That's what I did. Sanded and painted with high temp paint. Holding up nicely. There are some tips made by Jones company I believe that come powdercoated, but I didn't know before I did mine.