You heard it, i'm getting new piping for my exhaust, going to end it in a 5th gen muffler, I've got a ypipe at least the friend i bought my car from says I do do i throw in a hi flow cat while i'm at it? or keep it oem? Is it needed for power? If so how much is it of a gain?

I'm basically cleaning the car up to use it as a daily driver for the next 5 years so it's not a race car but i've figured why not upgrade when replacing parts?

Please share your thoughts.

 

No high flow cat...for what? they're

Stock is a highflow cat...

 

Dont bother...they are bad for the environment. Stick with the stock cat.

 

ok, thanks guys.

InsneDrmr i saw one that said it's OBD II spec I was actually going to go for that but it's so expensive for no real power gain as i'm understanding.

Is there any way to know if I need a new OEM cat? Car has 164,000 and I dunno if it's ever been replaced.

 

Grr to Cali Spec... sucks azz

 

It your cat is broken you would know. Your exhaust would sound like a bunch of little rocks in a metal can. Other than that the only thing I could think of would be the cat rotting out from rust. If none of these apply then just leave it be.

 

Not





10 currs

 

it would prolly smell bad....if its clogged ur car will run like ISH

 

Hi-flow cats are illegal, at least they are here in California or wherever else that requires a bi-yearly smog test. There's no considerable gain that can be attained, don't bother with it.

 

Yeah, like everyone else said, no performance gain + bad for environment, just stay away from them.

 

will a high flow cat change the sound of the exhaust in any way?

 

Depends on the rest of your set up.

 

unless something is wrong with it, then leave it alone. There are no power gains that result from a high-flow. The only reason I say high-flow over OEM is $$$ price (if it needs replacing)

 

I have a friend who gutted his cat after doing an intake and exhaust mod. The difference was very noticeable and there was no hint of raspiness. Just a little more throaty. This is very bad for the environment, but he lives in an undisclosed location that does not check for such things. Some test pipes are passed as "high flow cats" when they are nothing more than a metal tube with flanges. What you do is up to you. But don't waste money on a Random Tech. high flow cat. There are better mods you can do for that much $.

 

gutting a cat and not sleeving it is much worse for flow than a functioning cat.

 

i ordered the high flow from warpspeed. its obd2 compliant. ive got a cali spec car but i live in jersey so i really dont care. im really thinking about selling it and getting a test pipe.

 

NOT, you won't gain any HP, maybe 1 if you're lucky.

 

what about the custom enterprise test pipes? dynos show +11 hp

 

I can show you a dyno of my car stock vs adding a Stillen Intake.. wanna see it?

 

if u have one....how much was the stillen intake?

 

That's not with a completly stock system, that car the tested had modifications to the engine.

 

...and you'll pass emissions how?

 

what kind of mods? and approx home much additional hp on a stock maxima?

 

What does horsepower mean?

 

^^^ Lol!!!!!

 

I have to replace my cat because it is rotted out. I have fed spec should i buy a high flow or just oem

 

Haha emissions...Fl rocks...! Sorry, I had to pick on you guys.

Ehh, dont, not worth it. Unless of course you need to replace it like MaximaEvolution said.

 

Basically nothing. They're a waste of time that's about it.

 

The only reason you should EVER install a hi-flow cat is if you are boosted, or, your stock cat is bad and you need a cheaper alternative to OEM that will still pass smog.

If you dont qualify for either of those two, then dont buy a hi-flow cat.

 

I know a certain somebody who runs no cat and he notices a difference. He just slaps it on when he needs to smog it. He doesnt care about he enviroment.

 

that certain someone does not have a maxima do they?

 

I would put my retirement on the fact that a high flow cat does not flow significantly higher, if any at all, than a stock unit.

 

no kidding... man just look at the damn stock cat urself... its freaken 2.5 in/out..... thats larger than the exhaust piping.. including the y pipe itself..... like stated earlier unless you are boosted they do nothing....

 

After a invisible speedbump, I fukup all my exhaust. So, Ive no money, I remove the cat for a peace of pipe. So Ive no more cat, actually I notice a big difference in the way it sounds. Better? Maybe for someones... HP gain? I dont know, I dont have a dyno.

Im waiting for money, and ill get a oem one back. I care about the environment, that why since 6 months I did 1600 km without cat.

 

so um... i feel like a bad person now.. i'm getting headers and the y pipe, but running a straight pipe to replace the cat and resonator but keeping the stock muffler... the whole environment thing really got to me.. but down here in sunny fl we dont really have too much of a problem with pollution.. that is until holes like me put stuff on their exhaust... >_> uhhh yeah..

 

get the high flow... i have a setup which includes a frankencar shortram intake, warpspeed y-pipe, magnaflow cat, custom b-pipe, cattman cat-back...

at first the cat couldnt be changed because it was too rusty to move. b4 i got it torched, all i had was my y-pipe on with the rest of the stuff...

when i finally got the cat switched, it actually gave the car a tiny bit more oompf, and sounded a lilttle bit better

 

Hey guys here in NJ I PASSED emissions with Random tech cat no problem. Also had at the time Greddy cat back and Budget Ypipe. I passed at the inspection station in Secacus.

 

^ he was refering to how you would pass emissions with a test pipe.