Exhaust
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4th Gear
Joined: Apr 2021
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From: Arizona
Exhaust
I am new to being a Corvette owner. I have a 2021 C8 2LY Shadow Grey with memory lift and Magnetic Ride, silver racing stripe and hash marks with red interior. I did not order the performance exhaust as I was under the impression it was for the track. After reading some of the excerpts on the forum discussing the sound , I would like to know if there is anything that I can do to my C8 for the throaty growl without having to replace the exhaust. Thank you
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From: DFW Area TX
Advanced
Joined: Nov 2020
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From what I understand the computer puts a little more fuel in the system at startup and the NPP valves are open, then they shut and open at higher RPMs depending what mode you are in. I am about to install NPP delete modules so the valves are open full time. You leave the valves in place you just unplug them and plug in the new module which tells the computer they are still there and working so you don’t get a CEL. I will report back how it sounds?
Pro
Joined: Feb 2009
Posts: 516
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From what I understand the computer puts a little more fuel in the system at startup and the NPP valves are open, then they shut and open at higher RPMs depending what mode you are in. I am about to install NPP delete modules so the valves are open full time. You leave the valves in place you just unplug them and plug in the new module which tells the computer they are still there and working so you don’t get a CEL. I will report back how it sounds?
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Melting Slicks
Joined: Aug 2018
Posts: 2,014
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From: Clermont, Florida
From what I understand the computer puts a little more fuel in the system at startup and the NPP valves are open, then they shut and open at higher RPMs depending what mode you are in. I am about to install NPP delete modules so the valves are open full time. You leave the valves in place you just unplug them and plug in the new module which tells the computer they are still there and working so you don’t get a CEL. I will report back how it sounds?
Drifting
Joined: Jun 2019
Posts: 1,539
Likes: 575
From: Port Charlotte,Fl
The fuse on the C8 has 3 contacts so it's running something else on the car...It's been bandied about on this forum about a work around so the other item still has power....maybe do a search.
Melting Slicks
Joined: Aug 2018
Posts: 2,014
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From: Clermont, Florida
E-Ray, 3LZ, ZER, LIFT
Joined: Sep 2007
Posts: 34,982
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From: NE South Carolina
I am new to being a Corvette owner. I have a 2021 C8 2LY Shadow Grey with memory lift and Magnetic Ride, silver racing stripe and hash marks with red interior. I did not order the performance exhaust as I was under the impression it was for the track. After reading some of the excerpts on the forum discussing the sound , I would like to know if there is anything that I can do to my C8 for the throaty growl without having to replace the exhaust. Thank you
There is one way you can bypass the muffler electronically- with a motorized cut-out! Just checked eBay and you can buy a pair similar to what is shown for $150 to $200. Will have to cut into the exhaust pipe leading to the muffler and cut the motorized section of this assemble and weld to the opening. Then a pipe to lead out of the car. Good muffler shop could quote. As noted it comes with a FOB remote. One below shows twp FOBs BUT saw one on eBay for <$150 that paralleled to one FOB.
Last edited by JerryU; Aug 8, 2021 at 09:49 AM.
Race Director
Joined: Aug 1999
Posts: 13,281
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From: Bluffton SC via Canton Oh
Cold engine requires extra fuel for a few seconds to get the beast up and running. No you can't make that longer then the start up nor would you want to. Dumping that much fuel would kill gas mileage and damage the engine and other components from running too hot.
Race Director
Joined: Sep 2016
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Race Director
Joined: Sep 2016
Posts: 13,180
Likes: 10,527
The richer mixture on startup isn't to "get the car up and running," it's to heat up the catalytic converters faster, so they start doing their job quicker. It trades a very short time of higher pollution for a quicker ramp up to less pollution.
Instructor
Joined: Jun 2007
Posts: 249
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From what I understand the computer puts a little more fuel in the system at startup and the NPP valves are open, then they shut and open at higher RPMs depending what mode you are in. I am about to install NPP delete modules so the valves are open full time. You leave the valves in place you just unplug them and plug in the new module which tells the computer they are still there and working so you don’t get a CEL. I will report back how it sounds?
Race Director
Joined: Aug 1999
Posts: 13,281
Likes: 2,509
From: Bluffton SC via Canton Oh
I think it’s the same thing? Cars cold needs to get up to temp?