Do I need cat. converter.

Noticed I don't have a cat. converter on my exhaust on the car I just bought. do I need one, someone put a whole diff. exhaust on it, and took them off. will they hurt performance, should I get a hi-flow,stock, or just leave it off..thanks..sorry for the questions but I am new to these 3000gt's. I know on my trans am, I took it off and it freed up some hp..thanks guys...

Where do you live?

Cats generally suppress power... but in some States it is illegal to remove them (like in California where I live).

:werd: Check http://www.3sxperformance.com/exhaust-tt.asp about halfway down you'll see the Ultra-high-flow-cat. I've heard some pretty good stuff about that one.

It all depends on where you live, but I'd HIGHLY suggest getting a high flow cat... I know stealthee's gonna' call me a hippie tree hugger, but I really hate it when people gut their cats, becuase it exposes the environment to really bad exhaust emissions....

If you plan on going to a 3" aftermarket exhaust in the near future, than get a 3" high flow cat for it too, but if you plan on siticking with the stock exhaust, than it might be kinda hard finding a high flow cat, becuase IDK if they come in 2.75" ...

nah, im gonna beat Stealthee to it, tree hugger. There are only 2 reasons to have a cat.
1) you care more about the environment than George W.
2) you live in a state where they do emissions testing during inspections