[ItsChristianInHD]

Hey y’all,

(This is how Im spending my lunch break today, looking at things I’d like to buy someday ).

I want to add the NPP exhaust to my car (for looks and sound, if I’m honest).
I can’t find a good aftermarket exhaust that doesn’t sound “rice”. I love the sound of the stock NPP setup.

I can’t find any way to buy the NPP setup either as a cat back or axle back. I only found the entire system of course. Is there a part number for basically half the system?

https://www.gmpartsdirect.com/oem-pa...bC12Ni1nYXM%3D

If not, is there any aftermarket systems that sound close to stock? Every video I find, doesn’t fit my fancy.

I’m open to ideas.
Thank you!

[HCI2000SS]

IMO the V6 sounds quite a bit different in person than in videos, with an exhaust system. I've drove a few with the NPP, and personally I like my Flowmaster non NPP better without question.

[Mark114]

You could install the NPP exhaust but I don’t think you’ll be able to control the valves if your car didn’t come with NPP from the factory. You would probably have to wire the valves open or closed. You might be better off with a non-NPP exhaust.

[Bumbleboy92]

I got the stock exhaust from a ZL1, I had a shop cut it at the axle-back and they welded it on. Looks great and the sound did get a bit deeper, the valves are always open but I don't mind that.

[ItsChristianInHD]

Originally Posted by HCI2000SS

IMO the V6 sounds quite a bit different in person than in videos, with an exhaust system. I've drove a few with the NPP, and personally I like my Flowmaster non NPP better without question.

I wish you could test drive exhausts

[ItsChristianInHD]

Originally Posted by Mark114

You could install the NPP exhaust but I don’t think you’ll be able to control the valves if your car didn’t come with NPP from the factory. You would probably have to wire the valves open or closed. You might be better off with a non-NPP exhaust.

I think your right, in order for them to work you need the computer flashed.

[ItsChristianInHD]

Originally Posted by Bumbleboy92

I got the stock exhaust from a ZL1, I had a shop cut it at the axle-back and they welded it on. Looks great and the sound did get a bit deeper, the valves are always open but I don't mind that.

Interesting! Did you buy it new? Or I’m assuming from a junk yard or something?

[WhiteMale]

Can't add NPP to a car that didn't come with it OE.

[arpad_m]

It's gonna be an ordeal unless someone has already done it and can give you a part number list, plus you find a dealer or third party willing to flash a system upgrade for an NPP car's VIN. I'm not even sure the main body wiring harness will have the leads to the NPP actuators.

Honestly, I would probably just let it go and buy a quad tip AWE system instead.

[Bumbleboy92]

Originally Posted by ItsChristianInHD

Interesting! Did you buy it new? Or I’m assuming from a junk yard or something?

I found a guy near me who owned a ZL1 and was giving away his stock exhaust, the shop charged me $100 for the install. There are at least 50 or so people here and on Facebook who have theirs sitting in their garage who would let it go for like $50 though.

Don't buy stock exhaust new, it would waste a massive amount of money and like arpad said you could get an aftermarket exhaust that would sound nicer, have a quad look, and be cheaper.


I have been throwing around an idea of jerry-rigging a system to control the NPP valves and let me tell you it is a rabbit hole. Most of the solutions or ideas are from the CorvetteForum since Corvettes got the NPP system before us and kept using it up till the 2020 (I'm not sure if they changed it but they probably did).

First, there is Theta who sadly went MIA after so much development. He was probably the furthest into the NPP project as a singular person. You can read through that entire thing but be warned it leads to nowhere unless you have knowledge in electrical engineering or the sort. This used the original NPP actuators. (If you like reading of our cars or similar, he did a LOT for the CorvetteForum, since we get mostly everything from the Corvette's but a few years later is a nice read)

Second, there is CityOf9Gates who went the fully custom route and did his control through Arduino and some slight wiring/programming. I followed this but didn't have the time or patience after failing at some of the code lol. It may work but you'd need some type of fabrication to keep the system safe as it's on the undercarriage.

Third, there was g8germany who like his name was most likely from Germany. His thread is short but not very descriptive. He did include a proof of concept though so there's hope I guess. This also used the original NPP actuators. He says he did his through Arduino as well.

Lastly, and I actually want to try this out is Total Performance Racing who have made an almost plug and play harness. From their description, all you need to do is wire ignition power, ground, and a switch of your choice to the existing NPP actuators and it apparently works. This seems like someone who either went in Theta's footsteps or used Theta's work to make, Theta did say that anyone could make and distribute them so I don't think Theta would be upset if he's still around.


But yeah, that's the method I know of after looking into it occasionally over the years.

Now aftermarket though, there is one I know of and it's the most expensive but imo the coolest idea. NOWEEDS has a system that is essentially adding an exhaust dump at the touch of a switch with their own actuators and piping so it's not OEM style. But not everyone wants to pay $900 for a straight pipe essentially with a switch.

[OniCamaro]

Originally Posted by ItsChristianInHD

Hey y’all,

(This is how Im spending my lunch break today, looking at things I’d like to buy someday ).

I want to add the NPP exhaust to my car (for looks and sound, if I’m honest).
I can’t find a good aftermarket exhaust that doesn’t sound “rice”. I love the sound of the stock NPP setup.

I can’t find any way to buy the NPP setup either as a cat back or axle back. I only found the entire system of course. Is there a part number for basically half the system?

https://www.gmpartsdirect.com/oem-pa...bC12Ni1nYXM%3D

If not, is there any aftermarket systems that sound close to stock? Every video I find, doesn’t fit my fancy.

I’m open to ideas.
Thank you!

No way the NPP is better than all aftermarket exhausts. I have the NPP and like it and still telling you this.
If you want loud go MBRP, deep go American Thunder and for the best engineered sound quality try Borla(2 sound options).
The NPP is quiet and doesn't sound that good either(with valves open) until you go into higher rpms, then it sounds great. I don't like that, since how often do you really drive in high rpms? Videos will usually just show high rpm drives, that doesn't really translate to real life driving experience imo.

[John Simon]

We have lots of usable parts and accessories that can be used in camaro or other chevys and ford. To Visit our junk yard Click Here...

[Chutzpah]

It may just be me, but I prefer my NPP to not be NPP. I have the actuator(s) fuse pulled so the valves are always full open. I just don’t think the exhaust is loud or obtrusive until you start getting to around 3K rpm… which is in and around the time the valves open anyway. There’s zero drone on the highway.

As has been mentioned, If you’re goal is looks and some extra sound, a used NPP set up and a quad opening lower bumper section should do the trick (on the cheap).

[ItsChristianInHD]

Originally Posted by Chutzpah

It may just be me, but I prefer my NPP to not be NPP. I have the actuator(s) fuse pulled so the valves are always full open. I just don’t think the exhaust is loud or obtrusive until you start getting to around 3K rpm… which is in and around the time the valves open anyway. There’s zero drone on the highway.

As has been mentioned, If you’re goal is looks and some extra sound, a used NPP set up and a quad opening lower bumper section should do the trick (on the cheap).

I was considering the cheap way lol. I might just save the money for my SS upgrade next year honestly.