I'm looking for near stock volume exhaust at idle & cruise for the 09 Avy. Looking to handle 600-800 rwhp. Avy has factory 4 link plus Autoride (airbags) so it's TIGHT under there. ARH 1 7/8 with cats. Any ideas or suggestions are welcomed. Gotta do something because back pressure is building boost but not power. Besides I keep blowing header gaskets.

 

Big case Magnaflow (over 20" case length), with a 7" diameter bullet in front. If it'll fit, done deal.

 

Round or suitcase? I've had the 5x11 case DI/DO on the 03 and couldn't stand the drone at cruise.

 

Oval case. Some of the shorter ones won't deaden like the bigger cases. There's a big difference. DI/DO isn't exactly the best combo to begin with. I've got a SI/SO and it's just fine.