Im having a custom cat-back system installed tomorrow but I didnt see a muffler there that I like plus I think the stock muffler will help me keep the sleeper look. Will I lose a lot of hp by keeping the stock muffler or not? Do you think I will even be able to tell a difference in performance with the cat-back over stock? THanks

 

Uh stupid question, doesn't a 'cat back' system, have to have a muffler? It's supposed to replace everything from 'the cat, back'.

 

Does anyone know if I can use my stock muffler with a custom cat-back system. I need to know, thanks

 

What you're suggesting is not a cat-back system... it's a B-pipe. The B-pipe goes between the catalytic converter and the muffler. So, what you're going to want to tell the muffler shop is "Hi, I would like you to bend and install a custom free-flow B-pipe for my Maxima."

I hope that helps you some, oh yeah... a mandrel-bent B-pipe just may give yer car an extra 1-2 HP. If you buy something like a Stillen, HKS, or Apex'i full cat-back system (that is, a B-pipe and muffler), you *might* get an extra 3-4 HP over stock (1-2 more than just the B-pipe).

Good luck pimpman

Justin

 

Ok so with the muffler is the cat-back system, because that is what I was originally going to do. But they wanted over 300 bucks for the full cat-back system and they didnt say anything about me just using the stock muffler. So your saying that 300 bucks for a full cat-back system would only get me 3-4 hp? Man that sucks. Let me know, Thanks

 

I would concur that a cat back system is only worth about 3-4 hp. I didn't dyno my car before/after mine was installed but I witnessed a 5th gen on the dyno, which they disconnected the exhaust before the cat and it gained only 2 hp! If you're after looks and sound (it will be loud), the cat back is fine. But if you want to try and free up some power, go for the intake Y pipe setup, which may give you an extra 10-15 hp. I just had a 3.5" finisher welder on to my stock muffler and I'm very happy with the looks, along with keeping things quiet.
Good Luck.

 

I agree that a cat-back system is really only for looks and sound.

Pimpman, it turns out that the stock exhaust from the cat back is pretty good. That's why a free-er flowing aftermarket system doesn't help much. However the exhaust system *before* the cat isn't very good, which is why a custom Y-pipe will get you *much* more power than a loud muffler. BTW most good Y-pipes cost at least $300... good products that make real HP aren't cheap.

Justin