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Just wondering if any members have a photo of the rear end of the C7 without the NPP option. I understand that it is 2 pairs of 3" tips with uneven spacing between the pairs.Thanks
 

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Thank you Glen for the clarification. I was kind of confused as I thought I had read about the uneven spacing in a thread in some Corvette forum.That is quite a relief as I had ordered the C7 without the NPP.
 

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There are two visual differences between standard exhaust and NPP. The standard tips are (4)3" tips, whereas the NPP exhaust has (4) 4" tips. Additionally, the standard exhaust tips are not polished, whereas the NPP tips are polished. Will try and hunt down comparative pictures and post later.

Spacing between the tips on pre-production version was sometimes uneven. It is even on production/for-sale cars.
 

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It still sounds decent without the NPP....heard a torch red 1lt last week ...sounds like my stock camaro...You have to remember you still have a huge 6.2 liter power plant that will make nice noise......
 

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Thank you Elegant. That clears up all the confusion on my end.

Hi Glen, sorry I am not a big fan of engine sounds, actually prefer a quiet exhaust.....I know this statement is gonna stir up some reaction. No offense meant to all the aficionados and purists.Just my 2 cts.
 

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AFAIK - NPP is just the stock code for the enhanced muffler.
 

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Thx glen, figured so. I heard stock exhaust has valves as well even.
The stock exhaust does NOT have the same valves the NPP exhaust does.

NPP: Two sets of valves. One set on each of the outer pipes, just behind the mufflers, open under certain conditions to make the exhaust louder. The second, known as AFM valves, are further upstream and close partway when the engine is in 4 cylinder mode. These make the exhaust quieter, not louder.

non-NPP exhaust: Has only the AFM valves. Even when they're open, the exhaust is quieter than the NPP exhaust when the NPP valves are open. It sound good, but is definitely not as loud or throaty as the NPP with the valves open.

NPP valves noted with Green arrow, below, AFM with red arrows. When the NPP valves open the exhaust gases bypass most of the muffler. With the non-NPP exhaust, all exhaust gasses pass through the full muffler path.

C7 Exhaust.jpg
 
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So does the NPP exhaust with outer pipe valves closed sound about the same as the non-NPP system?
 

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Hi cayennes:

Should have just PM'd me I could have solved your problem. There is a difference and the NPP looks much nicer from the rear. Smaller exhaust tips and larger gap in the middle to fill up the space I guess. I don't know that the 5 extra HP is worth the 1,200 to 1,500 dollar option price though.Have a great Christmas Allan and a good New Year.

STUNG:stung:
 

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Hi cayennes:

Should have just PM'd me I could have solved your problem. There is a difference and the NPP looks much nicer from the rear. Smaller exhaust tips and larger gap in the middle to fill up the space I guess. I don't know that the 5 extra HP is worth the 1,200 to 1,500 dollar option price though.Have a great Christmas Allan and a good New Year.

STUNG:stung:
The looks and the sound are the best $1200 - $1500 I spent on mine. Unless you are planning ahead of time to change your exhaust, it is the best money for an option you can spend on a new Corvette. If you are strictly looking for the five HP then it can certainly be found with a much cheaper mod, but for everything else the NPP provides nothing in that price range compares. My NPP is my most favorite one thing on my Corvette!
 
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