[David W]

Anyone running a catless Downpipe? Looking to buy a downpipe but don't know if I should go catless or not. It's cheaper and I heard more power but it's also louder and I want something quiet and was wondering if the smell is bad or not.

 

[aar0n]

Catless is illegal if using on a public road I believe. Yes it will be slightly more power and you will get a CEL (unless you use a tuner that gets rid of it). It will not be quieter but may be louder. The smell will be worse than before if you are sticking your lips to your exhaust pipe since there is no cat.
I you are worried about the law, get one with a highflow cat but you will pay for the cat. if you arent worried about the law or it doesnt apply to you since you will not be on public roads then get a catless since it would be useless to have one.

 

[Chuckable]

aar0n is pretty much spot on. Removing your cat is illegal and will void your warranty. I've yet to see any comparisons of how much hp and tq are lost to a catted vs. non-catted downpipe for the FiST. If there is any difference, I would guess that it's very, very small. In my experience, no cat = smelly exhaust. But it's your car, enjoy it how you like it!

 

[lou5560]

Go with the Cobb catted downpipe.

 

[RodMoe]

A Catted DP will throw a cel unless you are running stage 3 OTS tunes or have a tuner or tuber software to turn off the p0420 code it will toss. Had both Catted and non dp both throw codes and with stock exhaust there won't be much change in the noise level. As for the smell non Catted will give you that hydrocarbon smell so there is that downside. But I find it not all that noticable all the time but it is there when the wind is right.. I think if any dp is warranty friendly it would be mountunes but that is only a guess on my part.. It's your car so enjoy shopping and modding your way..