Axle back install with NPP
Thread Starter
Racer
Joined: Feb 2015
Posts: 274
Likes: 9
Axle back install with NPP
So I have the NPP exhaust on my corvette. My questions isn't how to remove and install the new exhaust I have coming (BB Bullets) but if there is anything special I need to do because I have the NPP system. Once I have the bullets installed, do I need to remove the fuse for the NPP? Also is there a valve or solenoid that I need to remove since I will no longer be needing the vacuum that is used to activate the flaps? So basically anything I need to know about installing an exhaust on a car that has the NPP Exhaust?
Thread Starter
Racer
Joined: Feb 2015
Posts: 274
Likes: 9
Wouldn't it make more sense not to have that circuit alive if it's not being used though? Taking out the vacuum likes and pulling the fuse or just pulling the fuse would make more sense to me. Can some people that have replaced their NPP exhaust with an axle back or cat back chime in here? Thanks.
Also on a side note, I will be selling my factory NPP exhaust that only has 3k miles on it. Will that sell for anything on here?
Also on a side note, I will be selling my factory NPP exhaust that only has 3k miles on it. Will that sell for anything on here?
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Wouldn't it make more sense not to have that circuit alive if it's not being used though? Taking out the vacuum likes and pulling the fuse or just pulling the fuse would make more sense to me. Can some people that have replaced their NPP exhaust with an axle back or cat back chime in here? Thanks.
Also on a side note, I will be selling my factory NPP exhaust that only has 3k miles on it. Will that sell for anything on here?
Also on a side note, I will be selling my factory NPP exhaust that only has 3k miles on it. Will that sell for anything on here?
They will sell for sure, but they are hard and expensive to ship so you will have better luck selling locally.
If I was you, I'd keep them for a while to ensure you like those Bullets, and, consider your future mods before selling. I had Borla Stingers, they were awesome when I had manifolds and factory cats...ok when I went with headers & aftermarket cats, a bit loud, but ok. But when I installed a big cam, it was just obnoxiously loud all the time. It was fun at the drag strip or car show but horrible in traffic. People looked at me at stop lights like my car was broken.
On my c6 I went with cutouts (before NPP's came out) and stock mufflers so I can be loud or quiet, my choice.
Thread Starter
Racer
Joined: Feb 2015
Posts: 274
Likes: 9
You should cap the lines so you don't have a vacuum leak.
They will sell for sure, but they are hard and expensive to ship so you will have better luck selling locally.
If I was you, I'd keep them for a while to ensure you like those Bullets, and, consider your future mods before selling. I had Borla Stingers, they were awesome when I had manifolds and factory cats...ok when I went with headers & aftermarket cats, a bit loud, but ok. But when I installed a big cam, it was just obnoxiously loud all the time. It was fun at the drag strip or car show but horrible in traffic. People looked at me at stop lights like my car was broken.
On my c6 I went with cutouts (before NPP's came out) and stock mufflers so I can be loud or quiet, my choice.
They will sell for sure, but they are hard and expensive to ship so you will have better luck selling locally.
If I was you, I'd keep them for a while to ensure you like those Bullets, and, consider your future mods before selling. I had Borla Stingers, they were awesome when I had manifolds and factory cats...ok when I went with headers & aftermarket cats, a bit loud, but ok. But when I installed a big cam, it was just obnoxiously loud all the time. It was fun at the drag strip or car show but horrible in traffic. People looked at me at stop lights like my car was broken.
On my c6 I went with cutouts (before NPP's came out) and stock mufflers so I can be loud or quiet, my choice.
Drifting
Joined: Feb 2014
Posts: 1,418
Likes: 267
From: Pontiac Quebec
The vacuum comes from the back of the intake which is a pain to get to. My borla's come with a push insert that you cap the lines off at the rear when you remove them. That's all you do. I'm sure your came with them too. They kinda look like mini push pins 
Enjoy the new music
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