Can I make good power with cats?

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Dec 1, 2003 | 10:01 AM

99-LS1-SS

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From: Greensboro, North Carolina

Can I make good power with cats?

I am looking at headers and y-pipe. Will my car pass emissions without the cat's even with a good tune? How much of a power difference will I get if I don't have cat's compared to if I do?

Dec 1, 2003 | 10:09 AM

CHRISPY

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You'll need cats. I would go with the new Random Tech bullet style cats. Flow over 500cfm each and are small profile.

Cheers,
Chris

Dec 1, 2003 | 10:33 AM

onebadz

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From: Lexington, NC

I wouldnt think you would lose that much through a good set of high-flow cats. Maybe 2-4 RWHP. I would gladly sacrafice the little power gain for the ability to pass emmisions,no rasp,and no smell. Good Luck

WeS

Dec 1, 2003 | 05:34 PM

Damian

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From: Atlanta

You can make great power w/ cats. There are cars making upwards of 430 rwhp through cats and passing emissions.

josh

Dec 1, 2003 | 07:57 PM

Noyzee

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From: East Side Performance! mASShole

B-man makes over 420 with his set up, and it will pass with a tune, with good cats, but dont know how much it lost, but i would say 5-10 rwhp. I gaind 18 rwhp just taking out my stock cats. they accualy flow prety good.
Power can be made tho!

Dec 1, 2003 | 08:37 PM

jrp

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From: Valencia, Ca

with high flow cats compared to ORY the difference is pretty neglibile. and passing emssions will depend on what kind of test you have. sniffer forget it without cats.

Dec 1, 2003 | 09:46 PM

S2002S

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From: Albuquerque

It is unlikely you will pass emissions w/o cats (you also have to pass an inspection).

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Dec 2, 2003 | 12:29 AM

jrp

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From: Valencia, Ca

Quote:

Originally Posted by RPM WS6

Passing without cats is no problem at all if you only have the OBD scan test. You will need cats if you have the sniffer test though. Many places (outside of cali of course) don't even do visuals....

rub it in why dont you

Dec 2, 2003 | 07:52 AM

#10

Noyzee

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From: East Side Performance! mASShole

My car does a plug test, and passes, but visual i throw cats on for.
Emmisions suck!!!

Dec 2, 2003 | 08:22 AM

#11

ShadowLightCSU

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I've heard of a few cars around here getting tuned extremely lean (I think that is what they have said) and passing without cats.

Dec 2, 2003 | 04:44 PM

#12

6shifter

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From: Palatine, IL

I just left my stock shiznat in there.... who cares. I can pick up the 5 HP by farting as I leave the line.

Dec 3, 2003 | 02:57 PM

#13

z98

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*blink blink*

Dec 3, 2003 | 07:26 PM

#14

GrannySShifting

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From: Glen Burnie, Md

One of our 409 Iron block, twin turbo cars, runngin no cats, and no muffler just a 4" dump over the axle... blew clean in Md

You DONT NEED cats, but they help. Stock cars shoudl run effeciently enogu to pass without at least smog good enough