Is Stealth Mode Available in the LT1 Trim with NPP?
 

Hey guys, question for all, I am looking at an LT1 trim camaro with the NPP exhaust.
Is the "stealth" mode available under the touch screen?

As many others, I do not want to upset the neighbours at 5AM

Or is this a SS thing only?

Cheers,

Jason

Any Camaro with the NPP option should include all 4 of the exhaust modes (stealth, tour, sport and track). Either tied to drive mode or changed through the settings on the screen

Thank you for the info......It would actually be a deal breaker for me if it did not have it in the LT1 trim......too many houses close together where I live and it would echo and reverberate everywhere...lol

I don't have track mode on my 2021 LT1. Even with mine set to sport is it no loud while just driving thru the hood at normal speed.

But you can confirm you have stealth?

Jason

Even if it doesn't you can tune any of the modes to be "stealth" with HPtuners.

LT1 has stealth, tour, sport, and auto (follows drive mode). It does not have a track option. Stealth really quiets down cold start, which is pretty loud in tour or sport. Only catch is you have select stealth mode manually in the vehicle settings every time you want to use it.

Even with "stealth" mode on (valves closed 100%) it is still pretty loud in my opinion on startup, enough so I could see some do-gooder neighbors still getting mad. The loudness is made worse on a cold start since it retards the injection and spark timing and increases RPM and throttle on cold starts to help warm up the cats. The retarded timing (in my opinion) makes the exhaust louder as well.

I can't believe GM let the Camaro with the NPP out of the factory as loud as it is during startup, but that is what it took to meet cold start emissions I guess and there's probably no immediate noise level requirement.

I've never heard a non-NPP in person but I would imagine it is a lot more quiet, especially during the initial startup rev up. Also I believe the stock tuning opens the valves during startup for the supposed "cool rumble effect". Although I can't remember it might close during startup if you force stealth mode, which you would have to force it through the menu, since I think it defaults back to tour mode (where the stock tuning sets the NPP valves fully open on startup) (like 6sigma said above).

HP Tuners can set the startup rumble and customize the opening on all the modes however you want it though.

Just tell your neighbour to be grateful that you don't drive a BMW M4.

M4 cold starts are even louder.

LT1 has Stealth, Sport, and Track.


I believe the Snow/Ice setting will put you on Stealth without choosing through the menus.

I don't have a stealth mode in my 2020 LT1. Have Tour, Sport and Snow/Ice...Snow/Ice and Tour sound exactly the same to me

I'm sure they are different, not at idle but at higher rpms. There is no 2020 LT1 tune in the HP Tuners repository, but 2017-2018 stock tunes and mine all indicate a difference.

https://www.chevrolet.com/content/da...art-072319.pdf

This is correct I looked and I have this option in my LT1.

FWIW,

My 2020 SS with NPP is just as loud on startup no matter what mode I turn it off in. And it will not let me change modes unless the car is started.