Keep seeing "NPP"...
Burning Brakes
Joined: Apr 2008
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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.
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St. Jude Donor '15
"In honor of jpee"
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.
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.
Drifting
Joined: Jan 2008
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From: Payson AZ
And F55 over Z51.. no comparison unless you are tracking..
My two cents..
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Burning Brakes
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From: SF Bay Area CA
Drifting
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From: Alton/Godfrey IL
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.
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From: HOPE is the first step on the road to disappointment.
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.
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From: Southern Utah
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!
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From: HOPE is the first step on the road to disappointment.
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From: Manitoba/San Jose del Cabo
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St. Jude Donor '11
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From: Southern Utah
MN6- 6 spd man
QX3- chrome whls
U3U- Nav radio
67U- Machine Silver
84I- Titanium Interior
41T- Black vert top
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Burning Brakes
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From: Margate, FL
St. Jude Donor '09
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.