hey guys just picked up a 05 vz sv8 ls1 and would like to give the car more of a note but want to keep it still rwc as its a daily driver ive noticed on ebay you can pick up a rear section with a more free flowing muffler for $250 or a full cat back exhaust with two center mufflers and a rear would something like the cat back system still keep in within the legal db rating anyone's experience or opinions would be great cheers

I've got an ls1 with an awesome note, I've got diffillipo 1 3/4 extractors, 100 cell ballistic racing cats and twin 3 inch xforce exhaust! Has a tuff note, not to sure if its legal, havnt had any problems so far!

Aftermarket catback will put you over the limit. I got EPAd a while back and put the standard cat back and cats on and kept the DF 4 into1s on. Failed twice then passed dead on the limit on the 3rd go. Was quiet as hell too.

Quote: Aftermarket catback will put you over the limit. I got EPAd a while back and put the standard cat back and cats on and kept the DF 4 into1s on. Failed twice then passed dead on the limit on the 3rd go. Was quiet as hell too. I don't agree with that, as long as you fit a resonator to the rear you should be o.k, I've heard these cars without a resonator fitted and they are definitely louder. My VY SS Commodore has a Redback twin 2.5 inch exhaust system & custom headers and it's as quiet as a standard system, it's quieter than a lot of riced up 4 cylinders around , no one would know that the car was a V8 unless they knew the car or saw the SS & V8 badge on it , many thought it was just a six. Yeah, if you're talking about a twin 3 inch system then yes,that would be too loud.

I've got pacemakers 1 7/8 primaries into 3 inch full stainless x force system on my vt ls1 sounds tuff as but I don't think it's legal