: Cats or no cats? Hmm...

05-07-13, 10:32 PM
Hey everyone,

I'm thinking about Stainless Works headers to go with my previously installed Stainless Works cat back system. But what I need some help on is whether I should get the high flow cats with the headers or not. I don't have any emissions inspections to worry about here.

Has anyone heard both? If so, how much of a sound difference is there (tone and volume wise)? Is one going to be harder to dial in on a dyno than the other? This might be a dumb question, but would each setup require a different plug than the other? I was originally thinking TR7ix.

Other mods already installed: CAI, 2.5 upper, ID850 injectors and tuned for all those.

I guess I'm not really worried about how loud it is :yup: Any input would be appreciated. THANKS!

Me Wanna A V
05-08-13, 12:17 AM
I'll keep this simple...

Cats: Cost more, slightly less noise, prevents some raw gas smell, HAVE TENDENCY TO MELT AND FAIL.

Off Road: Cheaper, louder, more HP, more fuel smell, FAIL INSPECTION....

Since u don't have inspection, save your money and get "off road". Most every Cat Conv. fails with high HP applications, especially forced induction which creates a lot of heat and melts them....

Ask your tuner which plugs he wants in your car, as u will need a re-tune due to the headers....

05-08-13, 01:24 AM
Cats will get you to boost quicker for the slightly higher back pressure...No cats higher peak hp, lower mid power....

05-08-13, 08:29 AM
I would go withouot cats however your car is going to be SUPER loud.

You might want to put back on your stock catback with the headers. They flow very well, will not drone and still sound great at WOT.

05-10-13, 05:40 PM
No cats higher peak hp, lower mid range power....

This. Also, if you delete cats, expect more rasp in the exhaust, too. That was my experience.

V locity
05-11-13, 07:45 AM
Another alternative is to put a couple of bullets on the mid pipe instead of cats. I've been in one and it's purdy quite...