Cats or no cats?
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Last edited by eevette2001; Apr 13, 2015 at 02:29 PM.
Acct Suspended APR 2026 by request
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2020 Corvette of the Year Finalist (performance mods)
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boo hoo
... if you choose to run cats on your car that's totally fine but don't come in here and patronize those of us who choose not to
... if you choose to run cats on your car that's totally fine but don't come in here and patronize those of us who choose not to
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there is a good reason and if you read as much as you preach you would have seen it in my previous post... go ahead and boost your motor and leave the cats on and have one burn up and lose your motor over it... but never mind all the modding, that voids the stock warranty
Racer
Joined: Apr 2014
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Make zero sense to not run cats. It's not like back in 1975. New Z06/Hellcats, etc. seems to make more power than you could ever most likely use , and running cats. There are more responsible ways to make more power without being part of the problem. If everyone did that, we would all have emission testing mandatory everywhere. A C5 runs greats with cats, stock! I was stationed in the Navy in Long Beach back in 1972, and I didn't know there were mountains around Los Angeles until 3 months later after a big storm cleared the sky. It is definitely a redneck plan to eliminate them.
Last edited by REDHOTS; Apr 15, 2015 at 07:04 PM.
Melting Slicks
Joined: Jun 2001
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From: Chicago IL
My car is supercharged getting rid of the cats did wonders. But unfortunately I am getting rid of my bullet catback for something quieter. My car has a mild rich tune and i can smell fuel. But that fuel smell is minute compared to all the diesel from big trucks and various autos.
I wouldnt be opposed to running high flow cars but im not spending that kind of bread on cats.
I wouldnt be opposed to running high flow cars but im not spending that kind of bread on cats.
Instructor
Joined: Dec 2012
Posts: 190
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From: Springfield Ohio
Cats or no Cats
After reading everyones reply I think I will leave mine off. I had cam, headers and X pipe installed a couple of years ago and yes, the smell is a bit strong in a garage , but most guys actually like it. I was thinking maybe with high flow cats it might sound better..again this is a personal thing. Has anyone actually done this and liked the sound better with the cats. I would love to hear a sound clip of the two, with a cam and headers.
Melting Slicks
Joined: Nov 2013
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From: USA
After reading everyones reply I think I will leave mine off. I had cam, headers and X pipe installed a couple of years ago and yes, the smell is a bit strong in a garage , but most guys actually like it. I was thinking maybe with high flow cats it might sound better..again this is a personal thing. Has anyone actually done this and liked the sound better with the cats. I would love to hear a sound clip of the two, with a cam and headers.
-LT/x-pipe w/ high cats, stock ti exhaust, sony action cam mounted to car
-same setup, minus cats, on the dyno recorded on my phone
-new heads/cam (still no cats), dyno on phone
-new setup still, sony action cam mounted to car
You might be able to pick up the individual differences between cats/no cats and cam/before after. Overall the cats give the exhaust a smoother, more refined sound from my experience. Catless it's a bit more harsh, loud. Not a HUGE difference from my experience. Both sound good to me, take your pick.
Instructor
Joined: Dec 2012
Posts: 190
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From: Springfield Ohio
I don't have a true before/after video, but I have videos with the following setups:
-LT/x-pipe w/ high cats, stock ti exhaust, sony action cam mounted to car
-same setup, minus cats, on the dyno recorded on my phone
-new heads/cam (still no cats), dyno on phone
-new setup still, sony action cam mounted to car
You might be able to pick up the individual differences between cats/no cats and cam/before after. Overall the cats give the exhaust a smoother, more refined sound from my experience. Catless it's a bit more harsh, loud. Not a HUGE difference from my experience. Both sound good to me, take your pick.
2003 C5 Z06 Exhaust Rev Pulls - YouTube
2003 Corvette Z06 Dyno - YouTube
Yyy - YouTube
New Exhaust Vid - YouTube
-LT/x-pipe w/ high cats, stock ti exhaust, sony action cam mounted to car
-same setup, minus cats, on the dyno recorded on my phone
-new heads/cam (still no cats), dyno on phone
-new setup still, sony action cam mounted to car
You might be able to pick up the individual differences between cats/no cats and cam/before after. Overall the cats give the exhaust a smoother, more refined sound from my experience. Catless it's a bit more harsh, loud. Not a HUGE difference from my experience. Both sound good to me, take your pick.
2003 C5 Z06 Exhaust Rev Pulls - YouTube
2003 Corvette Z06 Dyno - YouTube
Yyy - YouTube
New Exhaust Vid - YouTube
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
Brand wise, I am not sure. Whatever Kooks uses in their X-pipes. Which I believe is a 300 or 400 cell cat, probably a decent quality one. They definitely helped with the smell once up to temp. Cold start you'll still smell it of course, but once it's up and running, no smell. I only had cats with the stock LS6 engine, so with a cam and such you might get some smell, depending on how much overlap your cam has.
I stayed catless and am happy where I'm at. The stock Ti exhaust is quiet, I'll take all the volume I can get. Still nice and quiet just cruising around. Don't mind the smell and there is no emissions checks here in FL.