up to how much hp can one really add?

 

3-5 .

 

it depends on all the other mods you have I would think...prolly on the order of 1-2whp

 

read = Not worth it.

I have a test pipe on my car. Take it fropm me

 

There is no way that a high flow cat produces 3-5 hp.
It might do 1hp at best, but probably not that much.
High-flow cat converter=waste of your money

 

ok, cause i saw one on ebay that claimed to add 9-16 hp, and found it hard to believe

 

i heard that you acutally might lose power in the upper rpm band.

 

i had one. then replaced with a stock, no difference! only makes difference when boosted, but even when boosted, you prolly only get 5-6 max.

 

will it pass emitions?

 

I returned mine for Cattman Headers w/ Y-Pipe. HFC, ain't worth the money.

 

Just keep your stock cat, and use that money on something else...like FSTB.

 

i am not looking into it for performance. i just need a replacemtn cause my cat has gone bad.

 

well if your just going to want to replace it cause yers is broke then you can either go cheapo way and get a testpipe (non-resonated) or a better one, i have a regular old pipe with two flanges on it for a test pipe and like everyone else says it doesnt really make any hp increases but it does change the sound a little bit if your looking for a cheap replacement then go for the plain old pipe from ebay for like $20 otherwise get a resonated one from custommaxima but there kinda pricey

 

If your cat is in good working order, then maybe a couple of hp. But it's not something you can prove, 1-2 hp isn't even measurable on a dyno, it could just be dyno variance. I know when Random Tech first made their cats for Maximas, they claimed 9-12 hp. But they put a 3" cat on a 2.5" exhaust. And FWIW, Random cats aren't worth the money. They're local to me, and I know their suppliers, you'd save money by just getting a Catco (same core). You could get a universal Catco core and have your local muffler shop weld up the flanges. Way cheaper than the ~$200 for a Random.

On my car, I picked up 34 whp...But that's because my car is turbo and I picked up 2 psi by swapping the stock cat out for a 3" test pipe.

If you're not boosted, the cat isn't worth it. But if your cat is toast anyways, I don't think an aftermarket cat is much more than a factory one, so why no.

 

Ebay. For your application.

 

DONT GET HI_FLOW CAT!~~ waste of money and no gains.

 

there are two types of high flow cats one is just a bigger cat with less restrictions in it (plus new). Second is ebay type. The funny thing is that it's not even a cat it's a piece of pipe (test pipe, if you wonna call it that) with a resonator welded on there, so it quiets down your exhaust.

Both won't give you any noticable gains 1whp, lol. You might notice some gains if you are seriously boosted, or your stock cat just collapsed inside (I seen a car that wouldn't go past 20mph because stock cat was collapsed).

 

Just for the people who have not seen this thread and read it.... I am not looking for eprformance gains, my stock cats is gone, and i am trying to find a replacemnt.

Now a test pipe. Will that effect emisions? I want to be able to pass with no rpblems. IF now i might just go with a no-name cheao high flow cat off ebay. Is a cat easy to replace yourself? like y pipe?

 

You will fail emissions with no cat converter.

 

I got a Magnaflow from a friend for like $50. I only did it because I was replacing my exhaust and didnt want to mess with cutting the old cat off the stock b pipe. I had a test pipe and a stock gutted cat but went with the Magnaflow just to be legal.

 

not really worth the money