[tommcd24]

Hi All,

New to the forums, and (hopefully) soon to be a first-time Camaro owner, assuming the plant opens back up soon. I'm guessing my '21 may end up being a '22 at the rate things are going.

I've searched and there are a ton of NPP threads, but I'm looking for more info, specifically as it relates to a V6 3LT I have on order. Understanding that a lot of this is preference, but I also want to understand how/when the valves on the NPP open and close.

For example, I recently test drove a V6 with NPP and it sounded pretty nice. I'm sure it sounds even better on the V8, but I'm decided on the V6 for a handful of reasons. Back to the NPP, I then visited another dealer, who had an SS with NPP. I noticed very specifically when he started it up that exhaust was only coming out of two tips. Does that mean it was in "stealth" mode? Or is that normal?

How often do the valves open/close in use? From what I've read it sounds like this is drive mode dependent and may open when accelerating hard, but then close when cruising? Is that accurate. I haven't found anything that really gives any details.

As to Pros/Cons, this is what I've come up with from reading. Let me know what I'm missing or not thinking of.

Pros of NPP
- louder/deeper/better sound
- option for stealth mode for early-morning/late night don't wake the neighbors
- can program per drive mode to suit my mood
- better diffuser with NPP (possibly painted glass back vs. matte?)
- Less drone at highway speeds? I ordered a convertible, so an annoying drone when cruising would likely be even more noticeable.

Cons of NPP
- costs an extra grand
- more tips to clean/polish lol

Last but not least, and if you can reply based on V6 specifically, what kind of noise difference are we talking really? I know there are a bunch of YouTube videos but it's always hard to gauge difference that way do to variation in recording quality etc. If anyone has db ratings that's cool. Or if you've driven both and want to speculate that it's x% louder when active and y% quieter in stealth mode that works too.

Thanks much for any info!

[LT1ornothing]

I test drove a v6 some years back with npp, for a v6 it sounded nice. I've been in other v6 non npp and they sound much more quiet and deeper. My advice, if you plan on never changing the exhaust, get the npp. If you plan to do exhaust anyway, non npp will be cheaper. I know your set on the v6, but don't pass up a nice LT1 for about the same as you are looking to spend on a loaded v6.

[tommcd24]

A follow-up question I should have included in my original post:
is the stock exhaust comparable to NPP in stealth mode, NPP in active/open mode, or somewhere in the middle? I'm assuming somewhere in the low-middle range?

The V6 for me is part insurance cost, part fuel usage, part all-season vs. summer tires, part 335 HP is more then plenty (for me), but perhaps most importantly, I want the car loaded with features. There is roughly a $10k difference between the 3LT and a 2SS... plus I would have to buy at a mimimum another set of tires, probably rims too... which would be another couple grand.

[LT1ornothing]

Originally Posted by tommcd24

A follow-up question I should have included in my original post:
is the stock exhaust comparable to NPP in stealth mode, NPP in active/open mode, or somewhere in the middle? I'm assuming somewhere in the low-middle range?

The V6 for me is part insurance cost, part fuel usage, part all-season vs. summer tires, part 335 HP is more then plenty (for me), but perhaps most importantly, I want the car loaded with features. There is roughly a $10k difference between the 3LT and a 2SS... plus I would have to buy at a mimimum another set of tires, probably rims too... which would be another couple grand.

I didn't get to play with stealth mode on the v6, I'd imagine it is about the same as non npp at idle and part throttle. 10-4 on the loaded options desire. I went the complete opposite direction, no options m6 v8, haha. I can also relate to the $10K swing, I had to save for an extra year to afford the v8.

[link0]

Why not just get the v6 1LE. It comes with NPP, forged wheels, and lots of goodies.

[LT1ornothing]

Originally Posted by link0

Why not just get the v6 1LE. It comes with NPP, forged wheels, and lots of goodies.

Might not need the SS suspension upgrades I'd imagine, maybe already has a specific set of wheels in mind.

[HCI2000SS]

I have a 2018 V6, and couldn't find what I wanted with NPP so I got the non NPP. I then added a Flowmaster axle back for $500 and did the install myself. I like the sound of a good axle back over the stock NPP exhaust, but if you can swing the extra grand I'd definitely get it

[LT1ornothing]

The V6 with npp sounded best 5Krpm to redline, but part throttle and idle sounded good as well. Not raspy, and I didn't notice any drone. If anything, it was definitely one of the v6 acoustic sounds I have enjoyed most in the last few years.

[tommcd24]

Originally Posted by 1LEornothing

Might not need the SS suspension upgrades I'd imagine, maybe already has a specific set of wheels in mind.

I don’t think that is possible? At least I’m not seeing a 1LE package or add-on listed. Probably not an effective option for me anyway, I don’t really need stiffer suspension, etc. as I don’t plan to spend much of any time on track.

Just looking for a nice, responsive, sporty ride. I have and love my Harley, but my wife is less interested in long bike trips. The convertible is to some extent a way to get a similar “wind in my hair” feel but with more comfort for her.

And for everyone now wondering why a Harley rider is debating exhaust options... that’s a fair question. The Rhinehart true duals on my bike are plenty loud. There is no stealth option there lol.

Edit: just realized I quoted the wrong post. This was in response to why I don’t just get the 1LE v6.

[Malbjey]

I absolutely LOVE the NPP on my V6. It was on my short list of must haves for a V6 Camaro.



IMHO it's totally worth it. The valves do open at idle. If I change the modes from tour to sport during idle, you notice a difference. It's not a huge difference, but it's there. When you're cruising you don't notice much difference. The valves are closed in the lower RPM range. However they open a lot earlier if you step on the gas in sport mode. I think they open about 3.5K in sport? Where in tour it's about 5.5K or so? I dunno for sure, but that's what it feels like.



I'm very happy with it and have no desire to go aftermarket. The adjustable modes are worth the cost. It's absolutely perfect to me. No drone at all either.


I very much believe it's one of the best sounding stock 6 cylinder engine/exhaust combos on sale today.

[Bob RS]

I own a 2019 RS v6 and even without the npp the exhaust note for a v6 has to be the best sounding in the car industry. My daughter gets a kick out of the exhaust when it pops in between shifts when your on it. But I did notice while using the paddle shifters the exhaust sounds more aggressive along with the pops on upshifts and downshifts.

[The Maverick]

Originally Posted by Bob RS

I own a 2019 RS v6 and even without the npp the exhaust note for a v6 has to be the best sounding in the car industry.

Agreed! My non-NPP 2016 1LT RS was great sounding for a V6.

As for the NPP vs non-NPP question:

I am still on the fence. I went with the NPP on my 2021 3LT RS. It is definitely louder than the non-NPP exhaust, and it sounds healthy, but it also sounds (from the driver's seat, at least) a lot like every other V6 out there with a modified exhaust. The non-NPP exhaust was more distinctive sounding. So much so that I never got around to upgrading the exhaust system, after having window-shopped some axle-back options.

None of the NPP modes directly compares to the non-NPP exhaust. They truly are two different animals. However, I was surprised that the sport and tour modes for the NPP were pretty much the same at higher revs (I guess that is because the NPP exhaust fully opens up at higher revs when you have it set to tour).

While I didn't modify my non-NPP exhaust on the '16, I think it is possible that I may end up going with an NPP-compatible aftermarket exhaust on the '21...

Definitely test drive both, because unlike the V8 where the NPP seems like a must-have, on the V6 I think it is a closer question. Based on my experience, I could see someone potentially preferring the non-NPP over the NPP.

[Staves]

I don’t think are pros of a non NPP period unless you want no sound.

[tommcd24]

So last night I did more reading, watched more videos and decided to spend the extra grand on the NPP.

The first video below by JCS helped make up my mind as the stock segments sounded pretty quiet/boring/just ok to me, particularly the drive-by at speed starting at 2:28. I disregarded the Borla segments (although it sounds nice) as that was not part of my consideration.
Another stock exhaust video


A couple of NPP videos I also used in my decision: