Muffler Mod
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Cruising
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Safety Car
Joined: May 2000
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From: Albuquerque NM
Melting Slicks
Joined: Sep 2005
Posts: 2,670
Likes: 134
From: merritt island fl
C1 of Year Finalist (stock) 2019
2016 C1 of the Year Finalist
2015 C2 of the Year Finalist
When the valve is open, the gas goes (mostly) straight out the large pipe?
Thread Starter
Late Model Domestics
Joined: Oct 2007
Posts: 1,548
Likes: 46
From: Virginia Beach VA
Burning Brakes
Joined: Dec 2008
Posts: 818
Likes: 444
From: Maumelle, AR
Bringing this one back from the dead.
I'm trying to figure out a way to get under the ridiculous 103 db limit at NCM. On my C7Z with ARH catless mid length headers, stock x-pipe with stock cats, and Borla S-Type catback I was 106. I tried their on site exhaust tip mufflers and they didn't work. I have since installed an additional set of 200 cell count Magnaflow cats but I don't think it lowered the volume at all.
My thoughts are to put the stock catback on but I think in off the shelf form they will be just as loud as the S-Type Borla during WOT due to the majority of the gasses going straight through the valved pipe. So I need more of the gasses during WOT to go through the muffled pipe.
The two options I'm considering are removing the curved pipe completely or drilling a bunch of 1/2" holes in it. What do you guys think would yield better sounding results, hopefully under 103 db?
I'm trying to figure out a way to get under the ridiculous 103 db limit at NCM. On my C7Z with ARH catless mid length headers, stock x-pipe with stock cats, and Borla S-Type catback I was 106. I tried their on site exhaust tip mufflers and they didn't work. I have since installed an additional set of 200 cell count Magnaflow cats but I don't think it lowered the volume at all.
My thoughts are to put the stock catback on but I think in off the shelf form they will be just as loud as the S-Type Borla during WOT due to the majority of the gasses going straight through the valved pipe. So I need more of the gasses during WOT to go through the muffled pipe.
The two options I'm considering are removing the curved pipe completely or drilling a bunch of 1/2" holes in it. What do you guys think would yield better sounding results, hopefully under 103 db?
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,106
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Bringing this one back from the dead.
I'm trying to figure out a way to get under the ridiculous 103 db limit at NCM. On my C7Z with ARH catless mid length headers, stock x-pipe with stock cats, and Borla S-Type catback I was 106. I tried their on site exhaust tip mufflers and they didn't work. I have since installed an additional set of 200 cell count Magnaflow cats but I don't think it lowered the volume at all.
My thoughts are to put the stock catback on but I think in off the shelf form they will be just as loud as the S-Type Borla during WOT due to the majority of the gasses going straight through the valved pipe. So I need more of the gasses during WOT to go through the muffled pipe.
The two options I'm considering are removing the curved pipe completely or drilling a bunch of 1/2" holes in it. What do you guys think would yield better sounding results, hopefully under 103 db?
I'm trying to figure out a way to get under the ridiculous 103 db limit at NCM. On my C7Z with ARH catless mid length headers, stock x-pipe with stock cats, and Borla S-Type catback I was 106. I tried their on site exhaust tip mufflers and they didn't work. I have since installed an additional set of 200 cell count Magnaflow cats but I don't think it lowered the volume at all.
My thoughts are to put the stock catback on but I think in off the shelf form they will be just as loud as the S-Type Borla during WOT due to the majority of the gasses going straight through the valved pipe. So I need more of the gasses during WOT to go through the muffled pipe.
The two options I'm considering are removing the curved pipe completely or drilling a bunch of 1/2" holes in it. What do you guys think would yield better sounding results, hopefully under 103 db?
Burning Brakes
Joined: Dec 2008
Posts: 818
Likes: 444
From: Maumelle, AR
Awesome! Let me know what you come up with. I'm in no rush. NCM is a once a year track for me during LS Fest so not planning to go back until next Sep. None of the other tracks I go to play the stupid noise limit game.
Racer
Joined: Mar 2020
Posts: 458
Likes: 104
From: Brentwood
many updates on this? I’m picking up a set of mufflers this weekend to experiment with. My thought was why not cut out both the S pipe and the perforated pipe. With all the exhaust going into a big chamber it might slow the flow and resonate idk. Could also open up the flow like a straight pipe, any thoughts?
Burning Brakes
Joined: Sep 2019
Posts: 923
Likes: 155
From: North Port, FL
There's another discussion going on about this right now. You guys might want to get together. I think hes at the same point you are.
https://www.corvetteforum.com/forums...er-delete.html
https://www.corvetteforum.com/forums...er-delete.html