What is the best catback system for performance and not alot of sound at all. Someone suggested the Apexi but i have no idea.

 

Um, with or without a y-pipe?

And which y-pipe? That is the question. I have yet to hear anything I've liked with a Cattman jet-hot or Stillen y-pipe on a gen4...

 

With a Y-Pipe, Cattman performance Y-pipe, i have one sitting in my gargage waiting to be installed.

 

The Apexi WS would probably be the quitest. It has a silencer that can be installed to quite it down even further, or pulled out for increased performance. Ive even read one post where someone said it was TOO quite, and they didnt like it, but if quite is your thing, I would go for the Apexi. Just my $.02

 

The quietest option would be to go to a local muffler shop and have them make a mandrel-bent b-pipe from the cat and keep your stock muffler. This works best if you have a y-pipe and high-flow cat.