So Ive done my homework and searched the site's previous posts, but im still not quite finding the info im looking for.

Q: I'm in the market for a high performance catalytic converter and would like some info, advice and recommendations from anyone who has knowledge on the issue.

I just installed DC Sport 3-1 headers and a Magnaflow cat-back exhaust on my 99 2door V6. Id like to eliminate the "bottle neck" of the stock cat. Any info would be greatly appreciated. Thanks!!

 

if you don't have smog testing you can go with high flow cat or a test pipe. But if you want to be environmentally friendly then go with a high flow cat. Research there flow rate...some might flow better than others. I know few people who are running high flows but I personally run test pipes. They are ALOT cheaper

 

Winter is about over (Maine Winter!) so I'm ready to tackle this project- an update to old posts, Maine vehicle inspection rules out the test pipe, so I'm looking for a high-flow. I'm searching website sales now, but would love to hear from someone who owns a highflow cat and has an info they would like to share. Thanks!

 

Some so-called "high-flow" cats are little more than test pipes. Be careful you really understand what you find. There ARE high-flow catalysts, but they aren't the cheap ones on ebay. I don't have one, so can't help you firsthand with brand-names.

 

Do your inspections actually look at the cat, or just make sure there is no check engine light? Because its very easy to trick a o2 sensor into thinking there is a cat...........not that I would know.

 

Kinda varies- Go to a Sears, etc and you'd never pass-prob not even off the lot! Most indepedant garages prob look for a cat, if they have a lift they always throw it up. I have a Magnaflow system and priced one of their cats for this car-over 300$. Not even sure if its a highflow,
believe me, I'd love to run a testpipe, but short of having one the looks like a legal cat, I dont see it passing.

 

There are ways to make a cat into a test pipe............usually involves a very large screw driver or a pry bar and a hammer. Not that I am recommending you do this.

 

Let me ask you this- Is the stock cat on my car "bottlenecking" the exhaust system that much to spend $300-$400 on a highflow cat? What type of gains, if any am I looking at for replacing the old for new?
As you can see below, I've got the DC headers to downpipe, old cat and then Magnaflow system. Am I spending time on sumthing that isn't really gonna matter, or is this sumthing that I'm really gonna know where that $300 went?
Thanks guys! Love the site, the knowledge getting shared here is invaluable!!

 

I don't think there will really be a noticeable gain on a lightly modded engine like that. If you were running a turbo and making 300+hp on the stock cat then I would say yes it probably is a major bottle neck that needs to be addressed. But on your car I would say while it would help some, it probably would not be a noticeable gain. But that is just my opinion.

 

Yea, you are basically confirming what I was thinking. Makes sense to me, thanks man!