NPP Question
Thread Starter
Pro
Joined: Jun 2008
Posts: 678
Likes: 33
From: Los Angeles California
NPP Question
I'm about to pick up a set of used NPP exhaust for my 08 C6
I was wondering how can I tell if the exhaust is working before paying the person?
Another question is I don't have the vacuum lines yet, so is there a way to manually adjust the valves under the car so I can make the car quiet/loud for the time being, until NPP in a box arrives in the mail?
Thanks in advance
I was wondering how can I tell if the exhaust is working before paying the person?
Another question is I don't have the vacuum lines yet, so is there a way to manually adjust the valves under the car so I can make the car quiet/loud for the time being, until NPP in a box arrives in the mail?
Thanks in advance
Racer
Joined: Feb 2014
Posts: 349
Likes: 0
From: Austin Texas
St. Jude Donor '14
Just to clarify for you before you do this: you can't just slap on a set of NPP. They require a specific fuse and a tap for the vacuum line to pull the baffles.
A Mild-to-Wild kit may bypass the fuse (I've never actually installed one so I don't know) and allow you control without it, in which case you'd still have to tap your vacuum line to run to the NPP. As an aside, search google for "NPP in a box" - I'm pretty sure there's a kit out there specifically designed for adapting NPP to non-NPP vehicles.
A Mild-to-Wild kit may bypass the fuse (I've never actually installed one so I don't know) and allow you control without it, in which case you'd still have to tap your vacuum line to run to the NPP. As an aside, search google for "NPP in a box" - I'm pretty sure there's a kit out there specifically designed for adapting NPP to non-NPP vehicles.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
As you may know, there are at least two different methods of controlling the NPP, one being the Mild to Wild, and the other being Sunset Creations on here. Testing it off the car, I can only think of two things to look for: one is the flaps in the two actually move (which may or may not indicate that the vacuum "pots" are not damaged) and the second being to actually get a vacuum source to put on each of the resonator/mufflers at the inlet to test if the flaps actually close w. sufficient vacuum. Maybe a written agreement w. the seller that if they don't work on your car, there is/you can get a refund. Others will chime in.
http://forums.corvetteforum.com/c6-t...y-npp-car.html
http://forums.corvetteforum.com/c6-t...y-npp-car.html
Last edited by AORoads; Mar 25, 2014 at 06:04 AM.
Race Director
Joined: Jan 2011
Posts: 11,973
Likes: 463
From: Tonawanda New York
Just to clarify for you before you do this: you can't just slap on a set of NPP. They require a specific fuse and a tap for the vacuum line to pull the baffles.
A Mild-to-Wild kit may bypass the fuse (I've never actually installed one so I don't know) and allow you control without it, in which case you'd still have to tap your vacuum line to run to the NPP. As an aside, search google for "NPP in a box" - I'm pretty sure there's a kit out there specifically designed for adapting NPP to non-NPP vehicles.
A Mild-to-Wild kit may bypass the fuse (I've never actually installed one so I don't know) and allow you control without it, in which case you'd still have to tap your vacuum line to run to the NPP. As an aside, search google for "NPP in a box" - I'm pretty sure there's a kit out there specifically designed for adapting NPP to non-NPP vehicles.
Burning Brakes
Joined: Mar 2006
Posts: 891
Likes: 18
From: Dayton Ohio
Get one of these:
http://www.autozone.com/autozone/acc...ier=70116_0_0_
Use it to test the actuators (I doubt they are bad)
When you install the mufflers they will be in the open position until you can add some kind of vacuum source. Do not limit yourself to the factory control. There are several good ways to get vacuum from the engine back to the actuators.
Matt
http://www.autozone.com/autozone/acc...ier=70116_0_0_
Use it to test the actuators (I doubt they are bad)
When you install the mufflers they will be in the open position until you can add some kind of vacuum source. Do not limit yourself to the factory control. There are several good ways to get vacuum from the engine back to the actuators.
Matt
Advanced
Joined: Sep 2008
Posts: 60
Likes: 11
I just completed this mod on my 2008. I chose Sunset Orange's Exhaust Commander Elite. It allows you to open and close them without an additional remote and still control them by RPM's like the factory setup. Sunset Orange's customer service is second to none. Benjamin will answer your emails and even call you back almost immediately. He steered this novice thru it from beginning to end. Opening the vacuum port on the back of the intake maniford was the hardest part of the install. Mufflers will be open all the time without a vacuum source.
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,104
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
You can suck enough vacuum with your mouth to close the flaps. It's not rocket science nor does it require hi-tech equipment.
Just make sure that the NPP mufflers you're buying were OEM on an '08. The '09 and up have a different angle of the pipe on the passenger side and will not be a simple bolt in installation.
Just make sure that the NPP mufflers you're buying were OEM on an '08. The '09 and up have a different angle of the pipe on the passenger side and will not be a simple bolt in installation.
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Melting Slicks
Joined: Aug 2011
Posts: 2,715
Likes: 1
From: Central Florida
I just completed this mod on my 2008. I chose Sunset Orange's Exhaust Commander Elite. It allows you to open and close them without an additional remote and still control them by RPM's like the factory setup. Sunset Orange's customer service is second to none. Benjamin will answer your emails and even call you back almost immediately. He steered this novice thru it from beginning to end. Opening the vacuum port on the back of the intake maniford was the hardest part of the install. Mufflers will be open all the time without a vacuum source.
Ben did this for my car too and it works great. Even better than stock since you are able to control the rpm at which the valves open. And also as already stated Ben is a terrific person to work with. There is also a pdf file on his site that gives step be step directions on how to install along with explicit pictures.
