NPP Exhaust Technical Questions
Thread Starter
Instructor
Joined: Oct 2014
Posts: 124
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From: Walker Louisiana
NPP Exhaust Technical Questions
I searched for a diagram of all of the parts of the NPP exhaust, but wasn't able to find them. I know there is an actuator on both sides of the car on the axle side of the muffler. I also know that there is a 2.5" flap that is opened in sport and race.
Is it possible to cut the mufflers out of the factory exhaust and weld in replacement mufflers and the flap and valves still work or are they an integral component of the factory muffler?
I have access to a shop and have a family full of fabricators and could easily just replace the mufflers, but I need to know the complete function of the NPP system.
I did search and didn't see anything related to C7 cars in general other than just a discussion of NPP as an exhaust option.
Thank you.
Is it possible to cut the mufflers out of the factory exhaust and weld in replacement mufflers and the flap and valves still work or are they an integral component of the factory muffler?
I have access to a shop and have a family full of fabricators and could easily just replace the mufflers, but I need to know the complete function of the NPP system.
I did search and didn't see anything related to C7 cars in general other than just a discussion of NPP as an exhaust option.
Thank you.
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
I do have all of those drawings, but I can also quickly answer your questions!
1) The valves are on the secondary pipes immediately down-stream of the muffler. Translation, you can cut those mufflers out and keep those valves.
2) I would cut right after the AFM as several of the axle-back systems do. Some just go from the secondary pipes and even have AFM provisions, etc.
But for what you're wanting to do, you can scrounge single-in, dual-out mufflers, and weld those pipes/tips back on while keeping the valves.
If you need the diagram, I can look for it.
1) The valves are on the secondary pipes immediately down-stream of the muffler. Translation, you can cut those mufflers out and keep those valves.
2) I would cut right after the AFM as several of the axle-back systems do. Some just go from the secondary pipes and even have AFM provisions, etc.
But for what you're wanting to do, you can scrounge single-in, dual-out mufflers, and weld those pipes/tips back on while keeping the valves.
If you need the diagram, I can look for it.
Team Owner
Joined: Jul 2006
Posts: 97,155
Likes: 1,471
From: Calgary, AB. There's a reason why white was the only color offered on every year Corvette. Proud Canadian German Jamaican!
St. Jude Donor '09, '12-'13-'14-'15-'16-'17
I will look on ALLDATA tomorrow at work and see what they have.
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Drifting
Joined: Sep 2013
Posts: 1,505
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FYI, the muffler on the NPP system is dual chambered meaning when the valves are closed exhaust if forced back through a chambered portion that makes at least 2 90 degree turns. The outside of the muffler, the part the valve actuated pipe connects to, is a straight through design similar to a Magniflow.
There's a lot of engineering in the system, good luck modifying it.
There's a lot of engineering in the system, good luck modifying it.