ittlfly

Hey Guys,

I'm selling my 94 ZR-1 and stepping into a 2LT 2012 Grand Sport. It is not equipped with the dual mode exhaust. Can that be added without a lot of hassle and do they come up for sale here?

As you can tell I'm brand new to the C-6 stuff having two C-4's (including the Z) since 1992..

Thanks

RicK T

It can be added but it won't have the automatic functionality of a factory setup.

Assuming you want the dual mode function to work you will need some type of vacuum control system in addition to the mufflers themselves. We have few vendors that sell what is commonly referred to as "NPP in a Box" which will give you a vacuum source hookup and remote manual control. Here are a couple threads to read to get you started:

http://forums.corvetteforum.com/c6-c...st-choice.html

http://forums.corvetteforum.com/c6-c...p-exhaust.html


You also have a choice with the mufflers. You can use the NPP's or Z06 mufflers. The difference is the Z06's are a milder sound.....but even that can be modded by cutting the mufflers open and welding covers over the perforated pipe inside each one. Used Z06 mufflers usually sell for much less than the NPP mufflers. Most folks prefer the NPP's because they are louder and harsher than the Z06's, personal preference. And yes, keep an eye on the Parts section and the auction site, take offs come up for sale fairly often.

RicK T

Here's another vendor selling the original NPP in a Box system:

http://www.topflightrepro.com/corvet...formance.shtml

wiggins82abn

I added DMH electronic cutout to mine and it cost about 600 total cost to have it installed including parts. I highly recommend this setup. It puts the exhaust note in your control, and open cutouts sound amazing.

ittlfly

Thanks guys for the information. I'll cross a few bridges when I finally get the car in the garage.

ROD BROWN

I don't think theNPP exhaust is worth the money.You have to rev up pretty high thru the gears to open the npp.I have it on my car.It came with it but it seldom opens up.Just my 2 cents.Rod

haljensen

The NPP is an excellent exhaust and can be bolted directly to your existing mid-pipe if you purcahse a 2009 or newer NPP. You can buy it new from a Dealer ($1100+) or used from CF Parts for Sale ($650 to $900). Maybe run a WTB ad in the Parts For sale section?

You'll also need a controller for the exhaust also since your car doesn't have the computer control, I suggest the one from http://sunsetorangecreations.com/

haljensen

"Seldom opens up"?

You need a controller for the NPP so you can open the exhaust when YOU want instead of when the computer wants.

Or just pull the fuse and run the exhaust open all the time.

mikeCsix

I love the NPP exhaust. Its quiet most of the time as there is enough road noise already. Its great to hear it open up when I'm on the road course at Pacific Raceways or get a little aggressive when getting on the freeways around here. It opens about 3500 rpm's which is about perfect IMO. The car is pretty quiet until I jump on it and it roars to life!

johnebgoode

Can't beat that sound.......!!

Ralphyboy

I have an 06 vert. After I got it, I found a ZO6 exhaust for $450 with h- pipe. I found ZO6 manifolds and cats, and had the whole system installed with an NPP in a box controler. I change from one to the other when I want to. At about 3000 rpms, with the Vararam intake I have on the car, the whole system just seems to come alive, and the sound is sweet. Yes, you can go to this system from stock. Also, I might add, the ZO6 system is 3" pipe from front to back. I'm not sure, but the stock NPP may be 2 1/2 ", not 3 ".

vettenevodrvr

You are correct. The system will bolt right up to a manual car. An auto tranny car is another story, and will require modifying the over-the-axle pipes to fit. The Z06 system is quieter than the NPP system, unless you mod the Z06 mufflers by cutting them open and seal the perforated pipe. Also, the Z06 system is 3", but necks down to 2 1/2" right before the muffler. NPP is 2 1/2". The full Z06 system will give you more power than the NPP.

To the OP: Do a search and you will find much more info on the addition of the NPP to a non-NPP 'Vette, and Z06 exhaust conversion..

1Corvette

Congratulations on your new car! I put the NPP on my car with AR headers. It is quiet on the road (no drone) when closed, but when I want it, I can have the sweet music of the LS3 to get my Corvette fix. Sound is very personal, but all my friends sure like the way it sounds. I highly recommend the NPP system.

Ralphyboy

The ZO6 system that I have sounds loud enough for me. When the revs drop to about 1800, it does drone very noticeably, and requires a downshift to avoid this, but I usually have it in the open position, and everyone, even my GF likes the way it sounds. At highway speeds, I usually stay in 5th, or just hit the button on the NPP in a box to get rid of the drone. I wasn't aware of the fact that the stock NPP was louder. The ZO6 one is fine for me.

Nice Ride

I wouldn't let the lack of NPP be a deal breaker nor would I modify a new car to add it. Better to buy a Corvette with it as a factory option. If it isn't factory it may be a headache. It does sound good but you have to punch the car to get the RPM's up pretty high for NPP to kick in. NPP comes on for a moment when you first start the car but quiets back down quickly. I got NPP on my car not so much for the sound as the "performance exhaust" adds 6 HP.

FloydSummerOf68

Adding NPP and the functionality of it is VERY simple.

Put the exhaust on and then run a rubber hose up to a vacuum line. No big deal and you don't need to spend money on the NPP in a box thing if you just want it to open and close like factory.

My shop installed Z06 mufflers with the full 3" overaxle piping on my A6 car and ran the vacuum line for $150 bucks. If I want it open all the time I just pull the vacuum line off and plug it. Takes about 30 seconds.

I tend to just let it open and close as it sees fit though. As soon as my car hits boost they open right up.

Jazc9

Where did you buy the exhaust for $450.00? I've been looking but can't seem to find it for cheap.

Thank you

drivinfast

Mine is set up the same way....

Just to clarify-------you paid for the Z06 exhaust and then $150 for the install?

Here in Houston, a few years ago a shop on north side of town did a lot of Z06 upgrades to bullets, corsa, borla, etc, there was a big pile of Z06 mufflers out back, they were practically giving them away back then.

gmanc606

Pull the fuse, or get the remote or get the old school dead pedal switch . I have dead pedal, and I love it. My 2 cents

gjjcvette

Do you have any drone at around 2000 RPM? I am asking because I took off the axle back. So, it was stock all the way before the last section, with the over-axle pipe and mufflers. I took off this last section and drove my C6 2008 manual around town. When reaching 1800 - 2000 RPM (like when shifting from 1st to 2nd gear), even slowly, the drone inside the cabin was so loud that I couldn't actually hear the great sound generated outside. I was thinking that, perhaps with the cutouts, since the rest of the system remains unchanged, the part behind the cutout "acts" kinda like a Helmholtz resonator (also known as branch resonators) and would eliminate this drone.

Anyone has thoughts about this???