Adding NPP Option
I was wondering if the hardware for NPP is available in kit form and be installed on an existing car.
If so, is it a bolt on? How much wiring or vacuum line installation is required?
Thanks for any help in advance.
Much discussion here about NPP, often can be had here used...
Not too difficult - just vacuum hose to activate actuators (and electrical valve to open/close).
Serch is your friend
https://www.corvetteforum.com/forums...rchid=66763087
I was wondering if the hardware for NPP is available in kit form and be installed on an existing car.
If so, is it a bolt on? How much wiring or vacuum line installation is required?
Thanks for any help in advance.

Last edited by Chiselchst; Oct 6, 2017 at 02:24 PM.
I was wondering if the hardware for NPP is available in kit form and be installed on an existing car.
If so, is it a bolt on? How much wiring or vacuum line installation is required?
Thanks for any help in advance.

bought my mufflers for 500.00 and my NPP in a box for 180.00 , 50 bucks at a local muffler shop to hang the mufflers and i installed the NPP
best of both worlds , loud when you want and quiet when it has to be
Dave
charges labor and carries insurance
) will often be somewhere in the "teens" for a complete job start to finish.Price always depends on what condition the mufflers are in and where they come from.
Not all years fit all cars.... The mufflers you get on e-bay..... May (or may not) match your x-pipe even if they are 2.5 inches
just because your originals are 2.5. With most installations we do, we also provide an x-pipe that matches, as it does not much of the time.
Many people bring us 3" ZO6 mufflers.... But they don't fit the automatic cars and even if it's a stick....they won't
match your x-pipe. Often, we provide a FULL 3" C6 ZO6 exhaust from the manifolds to the muffler tips....with a controller.....
Please people, before you trash someone's business, price, or products..... Please know EXACTLY what you are talking about.
Most time we explain that a "from scratch" NPP install is usually about the price of a new BORLA STINGER install... Only
you can turn the sound on and off with NPPs.
Chuck CoW
The Best of Corvette for Corvette Enthusiasts
charges labor and carries insurance
) will often be somewhere in the "teens" for a complete job start to finish.Price always depends on what condition the mufflers are in and where they come from.
Not all years fit all cars.... The mufflers you get on e-bay..... May (or may not) match your x-pipe even if they are 2.5 inches
just because your originals are 2.5. With most installations we do, we also provide an x-pipe that matches, as it does not much of the time.
Many people bring us 3" ZO6 mufflers.... But they don't fit the automatic cars and even if it's a stick....they won't
match your x-pipe. Often, we provide a FULL 3" C6 ZO6 exhaust from the manifolds to the muffler tips....with a controller.....
Please people, before you trash someone's business, price, or products..... Please know EXACTLY what you are talking about.
Most time we explain that a "from scratch" NPP install is usually about the price of a new BORLA STINGER install... Only
you can turn the sound on and off with NPPs.
Chuck CoW
it was assumed that the guy is buying a car without NPP and he wanted to add just NPP ....
one would assume again that the OP or you in this case would buy the correct set of mufflers that do not need a new X PIpe or bending to go around the transmisson.........
So with all that said, Yes $2,0000 is a crazy amount of money to spend to purchase and hang a set of axle back mufflers and add a NPP in a box .......
Dave
Last edited by Dcasole; Oct 7, 2017 at 08:13 AM.
Last edited by BadAV; Oct 7, 2017 at 09:17 AM.
it was assumed that the guy is buying a car without NPP and he wanted to add just NPP ....
one would assume again that the OP or you in this case would buy the correct set of mufflers that do not need a new X PIpe or bending to go around the transmisson.........
So with all that said, Yes $2,0000 is a crazy amount of money to spend to purchase and hang a set of axle back mufflers and add a NPP in a box .......
Dave
Dave.... Assuming you get the RIGHT MUFFLERS, AT THE RIGHT PRICE, INSTALL YOURSELF, and PAY NO SHIPPING.....
AND have no complications.... Sure, you can score an NPP job under a grand....... Most people should be sooo lucky.
While you might not have intended to trash my business, but your comment.....
Dave
Yes, at HOME DO-IT-YOUR-SELF NPP installs can be under $1,000. I've seen a few.
If you're going to "tell the shop you want NPPs." and let them locate them, be sure they fit the car....provide an x-pipe that matches,
(good clean NPPs of the right year and size are often tricky to find and 3" don't fit most cars (with more mods), install them, install the
conversion box.....etc... All the while, like any REAL shop..... Provide the labor and misc parts.....
Don't expect the final cost to be same as you would pay if you did it at home with your buddy and a case of beer.
I think it's fair to say that....
No offense taken.
Chuck CoW
So I guess the "miss" here is that that I assumed ...
We also don't want to mislead those that might have the skills to do it in the garage with some beer and a friend like I did ....

Dave

If I realized how easy it was to just remove the manifold I would have skipped using all those nasty words
which resulted in some really bad looks from my wife and getting the nasty cuts on my hands 
Dave


He installed them himself on his Base C6 and then paid somewhere around $200 for a 'NPP in a Box'.
So, I guess his total price was aound $550
BTW ... The NPP was a $1,195 option on my GS.


He installed them himself on his Base C6 and then paid somewhere around $200 for a 'NPP in a Box'.
So, I guess his total price was aound $550
BTW ... The NPP was a $1,195 option on my GS.
best mod i have done on the car .....
Dave


After I installed a set of catted headers, the car was so damned loud when the NPP valves opened up at wide open throttle that I finally replaced the NPP with a set of Borla 'Touring' mufflers ... noise problem solved
The NPP was just fine with the headers during normal driving, but again, it was obnoxiously load at full throttle (valves open).
I love the sound with the headers and the gates open ....but when I am tired of it ... I just close them ...

Dave
No your not. When I got my GS it had the stock exhuast on it. I was looking for a C6 with the NPP. So I didn't look long enough to see what would be required to make that happen if it could so I bought a Corsa extreme exhaust which was great. I knew I was going to go with headers and cam. So it is a great option. I picked up a set of NPP mufflers with muffler mod off here and installed the NPP in a box and never looked back. Sounds good just ready to get the headers (whenever they come in, ordered KooKs from a vendor got the headers but not the catted X-Pipe and Halltech) and cam installed.



















