I have a 2008 stock 6M coupe with standard exhaust.
I have been reading about NPP exhaust...I want to convert.
What components are different (what parts would I need to buy) to convert to a factory NPP install?
How much horse power will I gain?
Will the conversion require me to tune my car?

 

You need to either buy B&B's dual mode system or find a used set of factory NPP's here on the Forum or on that auction website. NPP's from a '08 C6 will bolt right on. Later years or Z06 sets will require modification. Several Forum venders supply the kits to make them operate with Mild to Wild switches. You'll love the sound when they're open.

The factory says 6 hp gain and no tune required.

 

Good question.....now I'm wondering if they would bolt on to a LS2 without modifications?

 

Do I just need to change the mufflers?
Are all the pipes between the mufflers and headers the same on my car with or without the NPP option?

 

Yes, you need to change mufflers. All pipes are the same, but you have to install a vacuum system to open and close exhaust valves. With open valves the sound is good, but inside you have drone... that is not so good.

I suggest you to buy others mufflers. On my 2008 C6 I installed Corsa Sport. They are really amazing for look and sound. Great sound & no drone

 

Thanks for the input. The "mild to wild" remote adder fits my split personality while conforming to my wifes mild personality when required.
How bad is the drone??

 

My Corsa Sport passed my wife-test.
How bad is the drone? It depends about your sensibility, but usually is not so good for hears and head...
Look for some friends with NPP or others exhaust installed and check them.

 

I would like to check out local cars...but there is snow on the ground till May. I don't know if I can go the winter without mods to my exhaust. Thanks for your input.

 

Do you plan to do the exhaust mod yourself?

 

They NPP or Z06 will fit the LS2. If you have an automatic there may be some fit issues but can be overcome, many threads about that.
I have seen many posts about Corsa and other systems having a drone, search and you'll find them. This is not just my opinion, the comments are there. You will find no comments about NPP/Z06 drone unless someone has left the valves open. Push the button and the drone WILL stop. The costs are significantly different too. BTW, Z06 are much easier to find and at a much lower price. Some folks cut off the 3" pipes and re-use their stock 2 1/2" pipes (the over axle pipes). I used the 3" and had my shop neck them down near the connection to the "H" pipe. Either way is very simple for a shop to do. Any bi-modal system is better than most because of the drone issue. I had Magnaflow and the drone drove me nuts on the highway. That system went to a friend's car and I did the aforementioned Z06 which I love.

 

I have the NPP and don't believe the drone is bad at all. I have the M2W but not in a hurry to install it as I can't imagine running it mild very often.

 

Yes, "08 LS3 NPP's will fit LS2's. Interestingly, If you find a used set try and get the intermediate pipes also, as they have a built in factory X-pipe.

Z06 NPP's will require the reuse of your existing overaxle pipes and they'll need to be welded to the Z mufflers. Also, the LS3 NPP's sound better.

 

How hard is the muffler swap, if you don't have a lift?

 

On a non NPP car it'll need a vacuum retrofit.

The kits come with wiring, mild-to-wild switch, vacuum line, vacuum accumalter, and vacuum switch.
vacuum source is ports on the rear of the intake manifold. Hose routes thru the center tunnel under the automobile, down the passenger side of the tunnel. vacuum reservoir and solenoid assembly mount to the inside of the rear splash guard or storage bin.
http://www.nakidparts.com/sitebuilde...es/npplite.pdf

 

I have owned both NPP and Corsa Sport. I really prefer the Corsa system. Less parts, better quality, and better sound. In my opinion the NPP is too quiet unless you cut open the mufflers and do the "muffler mod".
Also, there is absolutely NO Drone with the Corsa Sport, even with an auto trans.