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Discussion Starter · #1 ·
I am wondering if I can get some education on the NPP exhaust, how it works, and options for C7's that don't have NPP, like me. From my research I understand that C7's with NPP have two sets of electronic valves and they operate based upon driver selection. I also have researched that trying to put OEM NPP on a non-NPP car may be problematic due to wiring, software, etc. I have one set of valves just before the mufflers. I cannot really detect a sound difference in any of the driving modes so perhaps the single set of valves provides more performance than sound.

If I buy an aftermarket axle back setup do most of the new exhaust available just replace the single valve set up I have with their own? I assume I would still have single valve operation with their ports but insert my valves, right?

Is it possible that I can buy a bimodal aftermarket set up that would allow me to use my drive control for the first set of valves and then activate some kind of mild-2-wild switch for the second set of valves more or less replicating OEM NPP?

Am I confused.

Thanks,

Russ
 

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No I am confused, where did you get the one set of valves before the mufflers????
 

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forget all the stuff about the valves in front...they are used by the car to control drone for the AFM 4 cyl operation. Many have messed with them and by forceing them opened and closed , they get bad drone at diff speeds.

you only option is a after market exhaust or the NPP system and then, I'n not sure how it ties in with the harness and display.
 

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I climbed under the car and looked at them.
thanks bro, I just learned something. I need to spend more time underneath my car I guess?;) lol
 

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thanks bro, I just learned something. I need to spend more time underneath my car I guess?;) lol
Forget more time underneath your Vette and get more time behind the wheel enjoying it! ;):cool:
 

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Most likely with an aftermarket system, it's be open all of the time. It won't be tied into the driving mode selection interface.
 

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Russ; You might be able to find several aftermarket performance exhausts if you look, but the last time I did most of them were still under development. It was unclear to me how they were going to deal with the V-4 drone with "their" design? Perhaps some have come up with a good design, but IMO you need to "hear" what they have come up with before spending your money on it. I suggest you wait a bit until there are some reviews out on these new offerings and really get to know your car as it is. You might just find it's fine like it is. On the other hand, if you do want another exhaust system after owning your car for a few months maybe these aftermarket guys will have a good alternative for the OEM NPP by then.
By the way here are a couple of pictures of the NPP exhaust:
npp.1.jpg npp2.jpg
 

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Dealing with the v-4 drone is simple if you buy an after market exhaust. Simply go to a tuning shop and have them tune out the cylinder deactivation.
 

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Discussion Starter · #10 ·
Oh perfect Chip, thanks. I can tell you that non-NPP looks just like this except for the valve on the exhaust tips. I am not sure if the muffler cans are different but everything else looks the same including the V-4 valve.

Russ
 

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Dealing with the v-4 drone is simple if you buy an after market exhaust. Simply go to a tuning shop and have them tune out the cylinder deactivation.
Just don't go into Ecco mode.
 

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Exactly, and opposed to a tune, you still have warranty......
Done right a Diablo tune will not effect warranty but I get your drift. I don't believe I would tune simply to eliminate Eco mode.


Sent from my iPad using Corvette Stingray Forum
 

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I have the same problem as you.So it looks like we wait or just get an exhaust without the sport/ touring/ track mode etc.
I plan on just going and go with headers and be done with it.
 

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I tried to change my order (placed before the price increase) to get NPP but was unable to. Is there a way to have GM get me the parts/wiring to upgrade after delivery at the dealership?
 
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