High flow cats
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Joined: May 2017
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From: Plymouth, Massachusetts
High flow cats
I have a stock 2006 with Corsa extreme exhaust. My question is will i gain anything by installing high flow cats? Will it increase exhaust sound and increase hp.?
Last edited by Don07; Feb 18, 2026 at 11:01 AM. Reason: added info.
Retired & lovin' it!
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From: Jackson NJ
To get maximum advantage, you should also get a dynamic tune from a reputable Corvette specialty shop.
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From: Orange County, NY
Nobody makes a bolt on-high flow cat for this platform. You would have to do headers with a high flow catted xpipe. I've seen customers gain 20-40rwhp more or less depending on supporting mods & how spicy the tune is.
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Racer
Joined: May 2016
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From: Clinton, Illinois
Hi there,
Yes go with long tube headers and a new X pipe with high flow cats. I have Kooks all the out to the NPP Chevrolet exhaust. Sound great, cruises quiet until you open the throttle. That's when it sounds best! I also have an on/off switch to keep the pipes open at all times. Good luck!
Mike F.
Yes go with long tube headers and a new X pipe with high flow cats. I have Kooks all the out to the NPP Chevrolet exhaust. Sound great, cruises quiet until you open the throttle. That's when it sounds best! I also have an on/off switch to keep the pipes open at all times. Good luck!
Mike F.
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Most "high flow cats" are junk & don't have enough precious metals in them to do a good job, an exception to this would be Kooks "green" cats, they are of oem quality....a headers/x pipe/ tune would gain you some horsepower, just changing out the cats will not
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Then again, what does "enough precious metals.to do a good job" even mean? Are they going to catalyze as much as the OEM low.flow cats? Certainly not. Will they catalyze a non zero amount of exhaust? Absolutely. My point here is that there is no data testing most of these aftermarket high flow cats, and you can't just say "price = goodness".
I believe the looks cats to be better than the $30 ones I bought for my C4 race car. I don't believe the $40 ones will do nothing, and I do believe they'll.keep.thenfes down some. I also don't believe that it will do as good of a job as new OEM cats. I do think it will work similar to the very old and very degraded factory cars in my 92 with 140k miles and one cat rattling inside, lol.
At the end of the day, your choice to run a high flow, no, or OEM-like car is between you, your local regulators, and God. Do what you feel is best.
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I would say my proof is my Pa state emission test, oem & Kooks green cats will pass, the cheap high flow cats will not
Racer
Joined: Jun 2019
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From: Beautiful Florida
My car also has Cat back, Corsa exhaust. I removed the resonators and it made the sound louder and nicer. You get the best of both worlds doing that. You keep the original Cats and get a nice rumble too.
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From: Ulta Vista, AZ
There is a reason Kooks green cats cost what they do.
Agreed on cheap cats being a waste of time. Mostl to pass visual to be honest.
Resonators typically reduce bad frequencies like rasp. They shouldn’t make a tone or loudness difference.
Agreed on cheap cats being a waste of time. Mostl to pass visual to be honest.
Resonators typically reduce bad frequencies like rasp. They shouldn’t make a tone or loudness difference.