high flow cat

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lucas
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high flow cat

Post by lucas » Mon Feb 11, 2008 2:55 am

I have a 1993 ss and am wanting to change out the cat due to a nasty rock accident. would a high flow cat benefit me in anyway?

SubaruNation
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Post by SubaruNation » Mon Feb 11, 2008 3:16 am

just take it out :wink:

yeah it will benefit you
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Post by beatersubi » Mon Feb 11, 2008 4:49 am

I'm currently in the market for an aftermarket downpipe. I've been debating between catless or high-flow catted.

Now, I've heard that our cars can pass emissions w/o a cat (with a proper tune), but the token environmentalist in me wonders just how much power a high-flow cat would actually rob.
Anyone know or have experience with catted vs. catless exhaust?
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Post by BXSS » Mon Feb 11, 2008 7:12 pm

It should not make much of a difference in HP vs. a decatted exhaust.

I'm thinking about catting my SS too.
I have a 3" inlet/3"outlet Catco cat. in the garage, I just have to go put it on.
Last edited by BXSS on Wed Feb 13, 2008 2:27 pm, edited 1 time in total.
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lucas
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Post by lucas » Mon Feb 11, 2008 7:42 pm

i kinda need the car to have a cat on it sense i live in California, gay ass emissions laws. But a high flow cat would benefit better than a stock one, right?

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Post by 555BCTurbo » Mon Feb 11, 2008 7:51 pm

Yes...the high flow catalysts are excellent...and will definately assist with lessening the exhaust restriction.
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Post by dropdfocus » Mon Feb 11, 2008 9:29 pm

lucas wrote:i kinda need the car to have a cat on it sense i live in California, gay ass emissions laws.
Those laws are in effect across the entire country. Not all states or the counties within those states utilize the sniffer test yet. Most just have the visual inspection of the required parts for emissions control.
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Post by Arctic Assassian » Tue Feb 12, 2008 2:14 am

For the enviromentalist to use a cat is pure blasphomy. Catlytic converters change hydrocarbons and NOx into greenhouse gasses. The emissions inspection program is to improve air quality for HUMANS. Greenhouse gasses are very harmful to the environment, but not humans.
Take out your cat, prevent global warming. peace.
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Post by SubaruNation » Tue Feb 12, 2008 3:02 am

Arctic Assassian wrote:For the enviromentalist to use a cat is pure blasphomy. Catlytic converters change hydrocarbons and NOx into greenhouse gasses. The emissions inspection program is to improve air quality for HUMANS. Greenhouse gasses are very harmful to the environment, but not humans.
Take out your cat, prevent global warming. peace.
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Post by dropdfocus » Tue Feb 12, 2008 4:55 am

cows farts = heavy methane concentration = green house gasses

Yep, I said cow fart... :lol:
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Post by evolutionmovement » Tue Feb 12, 2008 5:06 am

Some state emission laws are more strict than others. California sets the highest standard and other states have followed: MA, CT, NJ, ME, MD, NY, OR, PA, RI, VT, WA. Surprisingly, the People's Republic of CO isn't in there! 16 states have challenged the EPAs denial that the state can set their own (stricter) standards in response to California's plan on regulating CO2 (which is really a way of regulating mileage).
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Post by Legacy777 » Tue Feb 12, 2008 8:53 pm

Arctic Assassian wrote:For the enviromentalist to use a cat is pure blasphomy. Catlytic converters change hydrocarbons and NOx into greenhouse gasses. The emissions inspection program is to improve air quality for HUMANS. Greenhouse gasses are very harmful to the environment, but not humans.
Take out your cat, prevent global warming. peace.
-Adam
I'm guessing you're joking around....but in the event you're not...

Not that I'm condoning one way or another for cat use......your statement about emissions and green house gasses is very misleading and mostly incorrect in my mind.

NOx causes smog, and acid rain, pollution, etc. Last time I checked, those are bad for the environment. Excess HC & CO, again, aren't good for the environment either.
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Post by dropdfocus » Tue Feb 12, 2008 9:00 pm

Here it comes... The tree huggers vs. the speak freaks! :lol:
Jason
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Post by SubaruNation » Tue Feb 12, 2008 10:16 pm

dropdfocus wrote:Here it comes... The tree huggers vs. the speak freaks! :lol:
ha ha i read both sides of that situation constantly and i'm still not sure what to believe... other than why would you put something in your car that will increase emissions.. like a cat. so i know that must be a point.

ish?
amen?
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Post by Arctic Assassian » Wed Feb 13, 2008 6:29 am

Legacy777 wrote:
I'm guessing you're joking around....but in the event you're not...


NOx causes smog, and acid rain, pollution, etc. Last time I checked, those are bad for the environment. Excess HC & CO, again, aren't good for the environment either.
It's six one, half dozen the other. I'm gonna die before the shit hits the fan anyways, call me selfish, but my car will forever be UHEV.
Kickin' it old-school.

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Post by asc_up » Wed Feb 13, 2008 8:13 am

I ran my car cat-less for about 2 weeks until I could afford a high flow cat. Once I got the high flow cat put on, I really didn't notice a difference in power.

Just throw on a high quality high-flow cat and you'll be fine.
-Aaron

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lucas
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Post by lucas » Thu Feb 14, 2008 4:27 am

so what im getting at is what kinda of cat should i buy, and the cat im talking about is where the downpipe meets the mid pipe right?

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Post by asc_up » Thu Feb 14, 2008 9:37 am

Yes that's the correct spot. Any high flow cat should work...
-Aaron

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[quote="evolutionmovement"]It was me. And those are my balls. Happy Sunday![/quote]

lucas
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Post by lucas » Sat Feb 16, 2008 8:46 am

thanks, team effort every one gets a gold star.

evolutionmovement
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Post by evolutionmovement » Sat Feb 16, 2008 6:34 pm

And don't throw out the old one - bring it to a recycler - you should get some decent money for it.
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Post by Subtle » Mon Feb 18, 2008 11:46 pm

I am definately not a tree-hugger-particularly when mountain biking or skiing. But, going into each "Earth Day", I avoid eating flatulent foods, or drinking beer. :roll:
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Re: high flow cat

Post by GTEASER » Fri Jan 16, 2015 10:39 pm

Sorry to bump up an old thread, but I just picked up an Invidia Bellmouth Catless DP for my '92 SS and am considering adding a hi-flow cat in the event that I manage to pass visual part of the CA emissions test. Of course I will hang on to the stock DP, but there is a possibility that the technician wont notice the aftermarket cat, and with it, the sniff test should pass fine. I don't want to have to change back to stock if I can help it.

Anyway, I have been doing a little internet searching, and most metal cats (not talking ceramic - too restrictive) are rated by the density of their stainless steel core, ie: 100, 200 or 400 (factory) cells per square inch. Will a 200cpsi cat be hi-flow enough for a forced induction application or should I find a 100cpsi cat?

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Re: high flow cat

Post by James614 » Sat Jan 17, 2015 8:23 am

I didn't know there was a standard to which they were rated. Every I've seen with one just says its a high flow, some say metal. I doubt most people know how dense theirs is.
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Re: high flow cat

Post by Legacy777 » Tue Jan 20, 2015 6:31 pm

This is a good article explaining CPSI.

http://www.carexhaustreviews.com/what-d ... stand-for/

If you can find a 100 cpsi high flow can that would probably give you the least amount of back pressure through the cat. Will a 200 cpsi work, sure. I couldn't however tell you whether you'd notice a difference in performance between the 100 & 200.
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Re: high flow cat

Post by GTEASER » Tue Jan 20, 2015 7:02 pm

Thanks Josh!

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