Steve9235

I have a 2017 C 7 1 LT it have the npp exhaust mode option
If you ordered it without that option what is the difference with the exhaust systems
Thank you

c54u

NPP has 4 inch tips and has electronic valves that open and close to give you quiet to loud exhaust sound which you configure.
NPP can be set to Stealth mode, Tour mode, Sport mode and Track mode.
NPP fills in the exhaust area much better than the Non NPP.

Non NPP has 3 inch tips and none of the above features. It is a standard non configurable quiet exhaust compared to NPP.


First pic - NPP
Second pic - Non NPP

Steve9235

Thank you

Corgidog1

Besides the difference in sound, the non NPP pipes look puny compared to the NPP trumpets.

Grand Slam

And the NPP is good for another 5 HP.

Patman

I disagree, I've seen them side by side and they really don't look like they are a great deal smaller. I definitely wouldn't classify them as puny.

sTz

^^^ I’ve seen them side-by-side too, and while “puny” might have been an exaggeration, the non-NPP is 25% smaller, and certainly look noticeably smaller in the valance cut-out.

I think the above posted side-by-side pics clearly illustrates the size comparison.

Pzilly

I agree and like both, I enjoy the look and function of my Npp but I also like the slightly more subtle (def not puny) look of the non NPP too. Plus if you want the flared tips you can buy nice add on tips. If your not into the louder exhaust sound I would skip paying the 1500 ish bucks for just 5 HP. I like mine and was part of the Z51 package which is a steal compared to just adding the NPP option.

dyoung

The flare on the end also makes them look bigger..The base system works just fine. Just think about all the loot GM raked in by having the NPP as an option. Getting to be a bit like Porsche.( But have a long way to go.)

dyoung

Yes, but it was an option on the 14 & 15 Z51's.

Patman

Here are the pics that I took of those two cars that I saw side by side at the same dealer and in my pics the size difference doesn't look quite as pronounced as the ones above.

Patman

Also, I just found out the inside diameter of the tips is only 1/4" larger on the NPP vs the base exhaust (3" compared to 2 3/4")

Carvin

Local dealer had a non NPP and it took 7 months to sell.

c54u

If you are referring to Addision (dealer according to plate frame), I was never there and the second picture is from Ohio.

Patman

Also, you mention the non NPP has 3" tips. They are actually 3 1/2" as measured on the outer diameter, compared to the 4" stated for NPP. I'm just trying to stick up for my base exhaust as I think it gets a lot of hate on here but it still sounds very good and when you measure the tips the truth is they aren't massively different in size. Despite the urging of many on here when I was placing my order, I do not regret skipping the NPP option one bit.

Greg00Coupe

I’m with you! I hate that I am forced to pay for npp that sound like a truck and sit in my basement until I trade the car. I run corsa extremes. Let me opt out of npp without giving up other features.

I had a sound clip of my 14 with base exhausts and it is by no means quiet.

dvilin

Certainly puny sounding. NPP or aftermarket exhaust is a must.

sTz

If I could have ordered the non-NPP for my Z06, then I would have. I replaced it with the Corsa system a week after delivery, which disables the NPP functionality.

There is certainly nothing wrong with either OEM exhausts, and it’s nice to have choices. If you’re happy w/the the sound and appearance, then that’s all that matters

c54u

I just presented the facts that were available to me from documentation, nothing else.

According to the 2018 Corvette buyers guide, 3" and 4" tips are correct.
My car is in storage so I can not go and measure the outside of the NPP tips. Maybe they are 4" may they are 4 1/4", I can't say. But I can say that the NPP tips fill exhaust opening considerably more than the non NPP.

Enjoy what you have.

http://www.corvetteblogger.com/docs/...orderguide.pdf

spireland

Wow, I didn't realize they are different sizes. I just thought it was the valve and the minor HP bump.