Exhaust ideas
Thread Starter
Instructor
Joined: Dec 2021
Posts: 150
Likes: 19
From: Greensboro, n c
Exhaust ideas
Planning on installing a new cat back system, probably a corsa of some type, but was curious, is it any performance or sound gain by gutting the catalytic converters? Thanks topkat 75
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,151
From: SW Florida
2021 C6 of the Year Finalist - Modified
Instructor
Joined: Sep 2015
Posts: 131
Likes: 54
From: Oregon WI
Don't do it man. A lot more smell, you get this tinny, raspy sound and minimal power gains to show for it. If you ever decide to go back you can't because you destroyed the cats you had which seem to be pretty hard to come by these days unless you spend lots of $$$. Ask me how I know.
Thread Starter
Instructor
Joined: Dec 2021
Posts: 150
Likes: 19
From: Greensboro, n c
Thanks Turbo6TA
I appreciate your input , I really don’t like the raspy tone a lot of these cars make, prefer the old fashioned deep muscle sounds, I was afraid to mess with the cats anyway, I’d like to keep the car as original as possible except for the way the stock is so quiet. Have a great day, topkat 75
Safety Car
Joined: May 2016
Posts: 4,667
Likes: 1,849
From: Erlanger, Kentucky
Headers and hi flow cats going into a stock exhaust especially the NPP is a great combination. Performance increase (especially with a tune) and will sound great. Quiet also when cruising, loud when you get on it.
Thread Starter
Instructor
Joined: Dec 2021
Posts: 150
Likes: 19
From: Greensboro, n c
It’s an 05 convertible. With Z51 pkg, 6 spd. 32 k and is quiet as a mouse unless full throttle, would like to hear it but want it to still appear as stock as possible, everything on the car looks like factory, belts, hoses, even battery is ac delco, lady owned and garaged most of its life. Thanks for input. Topkat 75
Safety Car
Joined: Sep 2007
Posts: 4,009
Likes: 491
From: South Florida
Really no noticeable gains from catback and even removing the cats completely. Maybe a couple HP at best for the cats. The stock mufflers flow plenty fine. I have long tubes, no cats, and stock NPP on my car. Super deep at idle, deep and snarly under 3500rpm, and above that it sounds like a monster. These are not muscle cars, they’re sports cars. They sound the way they should, different but awesome. The only other newer V8’s cars I really like the sound of when modded would be the HEMI.
Thread Starter
Instructor
Joined: Dec 2021
Posts: 150
Likes: 19
From: Greensboro, n c
Hey I get it, but I just like the old school deep sound of the muscle cars V8. I had a SS 2017 Camaro with flow thru mufflers and I loved the sound of that, thanks for your input. Topkat 75
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Melting Slicks
Joined: May 2020
Posts: 2,135
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From: North Little Rock, AR
I know you mentioned some sort of Corsa for the axel back. To my ear they have a higher pitched sound that other manufacturers. I went with the Borla S Type II on my car as it sounded better to my ears for what I wanted. My is stock with just the axel back. YMMV
Le Mans Master
Joined: Oct 2000
Posts: 6,503
Likes: 717
From: Sausalito CA
FWIW I would not gut, but find performance replacements.
(Too many complaints about fuel smells)
As for more power, probably just 1 or 2 Hp, if any.
Seat of the pants comment, no difference in power/ torque curves.
But, there are gains from weight loss
and to me, I hear a slightly higher/ treble tone, yet very (very) subtle.
Lastly, be aware of any visual smog test rules for road registration.
Good luck.
(Too many complaints about fuel smells)
As for more power, probably just 1 or 2 Hp, if any.
Seat of the pants comment, no difference in power/ torque curves.
But, there are gains from weight loss
and to me, I hear a slightly higher/ treble tone, yet very (very) subtle.Lastly, be aware of any visual smog test rules for road registration.
Good luck.
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,629
Long tube headers, high flow cats, sports level exhaust system.
Hence with high flow cats and long tube headers, something like the Atak/Extreme mufflers will be way too loud on the street.
And no, do not gut the cats, since without cats in play, will stick out the cabin of the car at every stop light.
As for the high flow cats (that allow a hell of lot more exhaust sound through without muffling it like the stock cats), total lose in HP will be less than 3Hp total, and again, no un-burnt exhaust gas smell.
Hence with high flow cats and long tube headers, something like the Atak/Extreme mufflers will be way too loud on the street.
And no, do not gut the cats, since without cats in play, will stick out the cabin of the car at every stop light.
As for the high flow cats (that allow a hell of lot more exhaust sound through without muffling it like the stock cats), total lose in HP will be less than 3Hp total, and again, no un-burnt exhaust gas smell.
Safety Car
Joined: Sep 2007
Posts: 4,009
Likes: 491
From: South Florida
The smell is subjective and on top of that the tune plays a big role. Windows up and I don’t even notice it. Windows down still don’t notice it unless I’m at a light and the wind is blowing from the back of the car to the front.
Burning Brakes
Joined: Sep 2018
Posts: 1,023
Likes: 174
From: Auburn Al
I appreciate your input , I really don’t like the raspy tone a lot of these cars make, prefer the old fashioned deep muscle sounds, I was afraid to mess with the cats anyway, I’d like to keep the car as original as possible except for the way the stock is so quiet. Have a great day, topkat 75
it does not sound like the OLD school muscle cars and it NEVER will. the firing order is different.
