Adding NPP to non NPP car?
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Adding NPP to non NPP car?
I have a non NPP equipped stingray and was wondering if someone has swapped or knows the best way to go about installing a set of OEM mufflers with the NPP and getting it to work. Also is the actuators by the tips NPP or AFM? And last thing are some OEM mufflers different diameters? Like one axle back may be 3” and another may be 2. something? I just want to make sure it’ll fit my 3 inch x pipe. Thanks any input would be appreciated.
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All the OEM NPP pipes and mufflers are the same size, including the ZR-1 (although it has some different muffler internals). It's not like the C6 where the LS3 cars were 2.5" and the LS7 and LS9 were 3"
The physical actuators for AFM and NPP are the same. Those used for the AFM valves are in the over-axle pipes. Those used for the "NPP" valves are in two of the tips...outer as I recall.
As for making it work....Someone used to sell a controller. You can do a search for "C7 Corvette NPP Controller" and it'll probably pop something up. It's an add-on system. At one point it was something like $1k for the box. Maybe that's fallen over time? I also recall seeing years ago someone posting DIY plans. They might be in one of the stickies in the C7 Gen forum. The factory controls are integrated into the BCM.
The physical actuators for AFM and NPP are the same. Those used for the AFM valves are in the over-axle pipes. Those used for the "NPP" valves are in two of the tips...outer as I recall.
As for making it work....Someone used to sell a controller. You can do a search for "C7 Corvette NPP Controller" and it'll probably pop something up. It's an add-on system. At one point it was something like $1k for the box. Maybe that's fallen over time? I also recall seeing years ago someone posting DIY plans. They might be in one of the stickies in the C7 Gen forum. The factory controls are integrated into the BCM.
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Maybe this is what you were referring to? https://www.akrapovic.com/en/car/pro...37&yearId=5445
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Thank both of you for the input I’ll be sure to look into that. I know akropovic make good systems. Is there anyone or threads of someone who has done the swap and I could use for guidance? Also regarding the size of the muffler pipes, what size are they? I have an ARH setup on my car (headers and x pipe) and the car came with a Borla exhaust when I bought it and after I bought stock mufflers to put back on they were the same size so I couldn’t slip one into the other and clamp it so my only option was to weld it. I thought they all were sized to slide into each other but they were both the same size.
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Joined: Apr 2000
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From: Texas
Thank both of you for the input I’ll be sure to look into that. I know akropovic make good systems. Is there anyone or threads of someone who has done the swap and I could use for guidance? Also regarding the size of the muffler pipes, what size are they? I have an ARH setup on my car (headers and x pipe) and the car came with a Borla exhaust when I bought it and after I bought stock mufflers to put back on they were the same size so I couldn’t slip one into the other and clamp it so my only option was to weld it. I thought they all were sized to slide into each other but they were both the same size.
Never needed to research itSounds like someone did something to the ARH x-pipe. The muffler pipe should slip inside. The x-pipes for ARH, Kooks, LG (which I have now), AFE (which I had) all work with the stock mufflers. As I recall, the muffler pipes are 2 7/8" OD but it's been years since I looked.
In the below pic you can see the factory mufflers going into the AFE x-pipe. Somewhere I have the same shot with the LG x-pipe.
