When pulling the #87 Fuse...
Thread Starter
Safety Car
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From: NJ
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Thanks ! I will check into that. 
Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
The NPP exhaust in track mode is designed to meet all FEDERAL sound standards. The federal test is a drive-by at speeds of up to 35 mph in the tallest gears that can be used at that speed. Even in track mode, the NPP valves close partially at speeds below about 36-37 mph in certain gears in order to meet this standard.
Pulling the fuse defeats the valves and they remain wide open at all times.
Pulling the fuse defeats the valves and they remain wide open at all times.
Bill
Instructor
Joined: Jun 2019
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From: Sacramento
I own a 2019 grand sport for about a year now. After reading about pulling the exhaust fuse, I pulled it. My corvette threw a code. It said to service rear axle or something to that effect. Took it to the dealer and the service tech said it was because I pulled that fuse. They replaced the fuse and all was good. Now I just keep my corvette in track mode under the sound management section.
Le Mans Master
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Just put a Corsa Extreme exhaust system on your Corvette. 
Thread Starter
Safety Car
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From: NJ
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Thanks. Right now I am treading lightly with the car because of the warranty. It only has 1,000 miles on it so I don't really want to chop it up with mods. I have a really loud modified C5 with headers, high flow cats and B&B Bullets. It sounds amazing. This car is docile in comparison. For the time being, I pulled the fuse and have just ordered the mild to wild.
Team Owner
Joined: Nov 2007
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From: Rochester, NY
I own a 2019 grand sport for about a year now. After reading about pulling the exhaust fuse, I pulled it. My corvette threw a code. It said to service rear axle or something to that effect. Took it to the dealer and the service tech said it was because I pulled that fuse. They replaced the fuse and all was good. Now I just keep my corvette in track mode under the sound management section.
Burning Brakes
Joined: Jul 2018
Posts: 752
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From: NW NJ
Thanks. Right now I am treading lightly with the car because of the warranty. It only has 1,000 miles on it so I don't really want to chop it up with mods. I have a really loud modified C5 with headers, high flow cats and B&B Bullets. It sounds amazing. This car is docile in comparison. For the time being, I pulled the fuse and have just ordered the mild to wild.
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Don't understand all the drama with the C7 NPP. Certain rpm's, certain speed, certain gear, different mph etc..On the C6 you hit 3500 rpm and they were open, period. Put in the mild to wild and it was open or closed. I have a 2019 GS coming from a 2013 GS and I can say the NPP in the C6 was way better.
Le Mans Master
Joined: Dec 2000
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The C7 NPP is certainly more complicated and less intuitive.
I suspect with the C7 GM was trying to more closely match what the driver is doing and the sound typically desired. Whether this is successful depends a lot of driver preferences.
Many would like an always open option but this would not be approved by the EPA as too loud.
A refinement I would like is sower opening of the NPP valves. The car is quiet and then WHAM it is loud. It sounds odd as this is not what engines do.
I suspect with the C7 GM was trying to more closely match what the driver is doing and the sound typically desired. Whether this is successful depends a lot of driver preferences.
Many would like an always open option but this would not be approved by the EPA as too loud.
A refinement I would like is sower opening of the NPP valves. The car is quiet and then WHAM it is loud. It sounds odd as this is not what engines do.
Race Director
Joined: Aug 2015
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From: SE WI
I actually like that they close in Track mode when I'm cruising on the highway below 1700 RPM. That would wear my ears out having to listen to that for long periods of time. Being a middle aged musician my ear drums have taken a beating over the years.
Racer
Joined: Sep 2019
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From: Hershey,PA
In 1966 I ordered a new Corvette Coupe with the side exhaust and in the summer after an extended road trip with the windows down (no AC) my ears would be ringing, but I loved the sound that exhaust made!!!!
Thread Starter
Safety Car
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Don't understand all the drama with the C7 NPP. Certain rpm's, certain speed, certain gear, different mph etc..On the C6 you hit 3500 rpm and they were open, period. Put in the mild to wild and it was open or closed. I have a 2019 GS coming from a 2013 GS and I can say the NPP in the C6 was way better.
Racer
Joined: Sep 2019
Posts: 375
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From: Hershey,PA
]
I'll be taking my '19 to the dealership later this month to have my stock non-NPP exhaust removed and have the BB Bullets installed. Can't wait!!
Sometimes all of these new fancy gadgets take away from the simplicity of a vehicle. I just want it louder. I don't want a quiet grocery getter. I tried a quiet exhaust on my C5 because I thought I would like it and I then removed it. Installed the B&Bs and it literally brought tears to my eyes upon the first start up. I couldn't believe it. It's like bringing a monster to life everytime you start it. And there's nothing like "hearing" your car do it's thing at all times. A Corvette should sound like... well... a Corvette.
I'll be taking my '19 to the dealership later this month to have my stock non-NPP exhaust removed and have the BB Bullets installed. Can't wait!!
Last edited by 62RPO582; Sep 7, 2020 at 11:49 AM.
Thread Starter
Safety Car
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From: NJ
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Instructor
Joined: Jun 2019
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From: Sacramento
Dvilin, I absolutely didnt pull the wrong fuse! I was very careful to pull the correct fuse. When I took my car in for service, the service adviser called me and asked if I had pulled the exhaust fuse. I told him I did pull it. I told him that I had read that it wouldn’t throw a code. The service guy said it will throw a code. He had seen it before and the same code came up. It was service rear axle if I remember correctly. He put the fuse back in and all has been well for a year now. I didn’t want to go against the advice of the service people so I just won’t pull it again.
Instructor
Joined: Jan 2020
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From: Cincinnati
I had a C6 with npp. I got mild to wild. Exhaust was open 95% of the time. On my C7 I pulled the fuse. I put fuse in car if for some reason I need to have a quieter car. I do think the C6 sounded better than C7
Instructor
Joined: Sep 2019
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From: Temple
I just installed the Corsa double helix mid pipe (14761) along with the Corsa NPP muffler kit (14776BLK), I already had the Mild to Wild. I prefer to leave the mufflers open as I don't think it's too loud (2019 GS Vert). Love the sound!
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