C5North

...what is that all about?

speedy_steve

It's the dealer code for the dual exhaust which became available on the '08 coupe and verts.

Steve

Bobz08C6

NPP is the GM RPO designation for the bi modal exhaust. Above 3500 RPM the valves open and increases the sound of the exhaust, improves air flow and adds an extra 6 hp to the 430. IMHO the two must have options are the NPP and the Z51 performance package.

dvilin

C5North

ok, cool. Thanks you guys.

Another question if I might.....

How does this exhaust compare to say Corsa Indy's?

danl72

AORoads

Don't know the Indys but know the touring and sports (is sport the Indy by another name?*). Both are very good and neither one seems to drone at any speed from what I've personally heard.

But to me the big differences are that the NPP is stock, and it is on when you want it, not all the time. That's just me but I don't spend it in places where I want lotsa sounds all the time.

* Must be me: I just went to Corsa site, for C6s; didn't see any reference to Indy.

azcanuk

If you want SOUND for 1200 bucks, but if you want performance for the cost of the NPP.. there a lots of ways to add way more than 6 HP for a lot less.. didn't waste the $1200 on my 08 and opted to put way more horses on for much less..

And F55 over Z51.. no comparison unless you are tracking..

My two cents..

adias

Actually... the valves open above 3500RPM no matter what, but... they will open at 2800RPM if the e-gas senses a fast throttle application.

LiquidDI

I had the Corsa Indy's on my C5. The NPP's are a deeper sound like borlas but drone a bit. Great thing about the NPP's is you can turn them off if they start to annoy you. Best exhaust system ever.

C5North

Thanks again for the info. My current arrangement is Blackwing intake, ported TB, long tubes, gutted cats and the Corsa's (perhaps called sport now, were Indy's in my day). At any rate all that stuff howls like HELL wide open and settles down quite nicely at cruise with no drone or resonance. Obviously the NPP set up won't be that loud but it sounds like they might be a nice way to go.

cclive

Corvette owners can refer to their options by code only because there are so few options available and we are completely **** about our cars! Mine is a vert, 3LT, MN6, QX3, U3U, 67U, 84I, 41T!

C5North

Oh believe me I get it. I have an '01. I'm just not up on all the C6 lingo yet.

C5North

And again, thanks for all the info you guys.

myownboss

what is all those terms?? i got a couple but not all!! hey is there a drone or resonaces problem with the BB Fusion on a 06 paddle shift??? Bob!!!

Racer

And the new NPP badges will be out soon...

cclive

3LT-trim pkg
MN6- 6 spd man
QX3- chrome whls
U3U- Nav radio
67U- Machine Silver
84I- Titanium Interior
41T- Black vert top

cclive

I'm getting ready to put on my new U3U badges over the weekend! Pretty soon you won't be able to tell what color the car is with all the badges on it......so I've ordered a 67U badge!

LS3Devl

You do not have to only have z51 to get the NPP. I have magnetic select ride with NPP as well !!

dingrao

Yeah, I didn't get the Dual-Mode exhaust either. I knew I was gonna throw on a set of stingers and headers within the first 8 months of owning the car, so I couldn't justify spending the extra coin for an exhaust I knew I was going to replace anyway.