I have 3" single stainless exhaust on my truck with a 22" magnaflow type muffler. I don't think it's actually magnaflow brand but its a straight through design. It got noticeably louder within the first 1000 miles but I'm wondering if there's more to come. I'd like a little more noise but I've only got about 3000 miles on the exhaust now. Is it going to change any more?

 

with a 22" muffler it wont be very loud at all. i've got a 14" maggie and its still way too quiet for me. but i didnt really notice much break in on my muffler. ive had it for about 5000 miles now.

 

It will get a tad louder over time, but you wouldn't rly notice it without recording the sound and comparing it to an older clip.