Jack Be Quick Racing

Help me understand what this option really gets me:

NPP Exhaust System Performance $1,195.00

I am looking at a Z51 coupe, manual, 2LT. What does this give me over the 'stock' exhaust for $1200?

So, it has 4" tips instead of 3.5" - what else of meaning?

Does the stock exhaust have a variable sound level setting, does this give me more choice, is it louder / more aggressive, any idea on what limited HP/TQ to look for from it?

Why would I do this option instead of a Corsa Extreme or Billy Boat?

I put Billy Boats on my BMWs and 2 chamber Flowmasters on everything else that's V-8 and American - so I know loud / aggressive when I hear it. How would the NPP compare?

I would hate to order this and then replace it with a $1500 BB or Corsa within three weeks of getting the car.

flange

On the C6, it gives you the option of a really refined, quiet car, verses the louder exhaust when you hit the throttle. Or, if you bypass it or buy the various mods, the choice of when you want them open or closed.

What it does for me is to keep peace in my development. Where I live, its really quiet. I mean pin drop at night. I can hit the button on the mtw and have the valves closed while driving through on my way in or out, then once I get to the main road, open the valves and let the ls7 talk to me. I can also close them at will as desired.

The aftermarket exhausts, in general are one way or another.

On the C7, its supposed to be changeable on about five settings based upon driving and your likes I think. to me, its was worth the extra Gee.

rcallen484

Electronically controlled butterfly valves that regulate exhaust flow depending on engine RPMs. Ask C6 owners, or better yet, find C6s with and without and compare for yourself (local Corvette club maybe?).

jamesw95

I loved it on my C6 with MTW. I would not buy another vette without it.

elegant

Right now the C7 NPP is estimated at +6 HP (per the Chief Engineer at the Bash), with actual numbers coming out within the next month.

Jack Be Quick Racing

Thanks.

On BMWs you can do what is commonly called the 'golf tee' mod - you pull the vacuum line, shove a golf tee in it, and both mufflers are open all the time. It is a 'little' louder . I assume the 'mild to wild' mod I read about here lets you open / close with a remote. But, is it anywhere near the sound of a Corsa Extreme or BB when it's open?

So there are those who think they'll be arrested at any moment with the golf tee mod and there are those, like me, that are removing the resonators and putting on Billy Boats or Esienbach race systems.

I might be further off center than most but, I like louder / more aggressive exhaust all the time - not drone - but real idle by car alarm setting off rumble.

Does the stock setup give this option and the NPP is just a little more aggressive at full open?

Again, I am not concerned about getting a new C7 and then replacing half the exhaust with an aftermarket - I am more concerned about spending the money twice to get the aggressive sound.

Sorry for so many questions, but there are very few modded Corvettes around me. A ZR1 that is pushed in and out of the garage on nice days. A Z06 that idles by on it's monthly 5 mile cruise. A few stock C6's that are dead quiet. One C4 with an aftermarket exhaust - louder than stock, not as loud as my BMW, Mustangs, Challenger, or FFR Cobra by any stretch of the imagination.

Jinx

It gives GM the ability to lower the base price by $1200 without actually affecting the bottom line, because nobody wants to buy the wimpy-sounding Corvette.

flange

many c6 guys just pull the fuse. you could do the gold tee method.

This isn't about fear of being arrested, rather there are many reasons for doing things. As stated, I live in a very quiet hood. its a respect thing for me. When I leave sometimes at five or six am for a drive ot the beach, why do I have ot be that guy with the loud car. I close the valves and all is well. If I am coming home after dark, same thing. its actually a nice feature.

With the valves open, it gives a nice sound, with little drone if any at least in my car. it isn't about the added single digit horsepower, its really about my car sounding like the 500 horse corvette that it is. cops follow me sometimes, who cares they like ot look at cars too.

rcallen484

Not in C7. Won't be vacuum powered----- electronic.

-CM-

There are a number of YouTube videos that demonstrate NPP with the Mild To Wild switch.

flange

did not know that. ok, then you can make a resistor network and drive them with a rheostat, lol. or just pull the wires.

JerriVette

The ability to have the car run quiet when appropriate and roar when you get on it.

It's minimal cost and integration into the corvette engineering are money well spent. Remember with AFM aftermarket exhausts will have extreme challenges to meet owners full expectations.

When i order a c7.... I will get NPP exhaust as well as z51, MRC and possibly the competition seat.

The only one I question would be the competition seat.

Being able to drive in stealth mode has a lot of advantages and then when the time is appropriate driving with a nice roar is awesome too. NPP gives you for 1200 dollars the duality of choice.

Leaving early in the morning or arriving home late I too do not want to be that guy ...and if I do...it's available with the NPP.

JmO

SCM_Crash

Funny. I ordered mine with NPP. My dad optioned his out without it.

Matt26

If you are going to replace the stock exhaust with BB or Corsa, then NPP is a waste.

BB has their fusion system which is essentially NPP.

rcallen484

He NEEDS to listen to both before deciding or just go with his gut if he knows there is no way a factory exhaust will be as loud as he prefers.

Jack Be Quick Racing

yep - agree. I went to the NCM Bash but with all the rain I didn't really get so see / hear much from the cars there at all.

Thanks for all the info.

jschindler

I've had B&B's on three Corvettes and NPP's on a Z06 and a Z51 C6. The B&B's sound better, but the better they sound on Corvettes the more you will get resonance at cruise speeds. Some folks are okay with it and some are not. The NPPs have gotten better over the past three years, with the ZR1's sounding the best.

Obviously it is all relative. You won't know for sure until you hear them. But the advantage of being able to open and close them is worth a lot.

DAFFYDRUNK

The AFM will dictate that the exhaust on these cars will be really quiet so you don't hear 4 cyl mode. This means NPP will be more relevant on this car than previous generations.
That said, I'd personally skip it and get electric cutouts if I want to be heard. Much cheaper, and the potential to be louder. Have a buddy that has it on his GTO and it can be stock quiet all the way to NASCAR loud.

The alleged NPP hp increase is not worth the money. ~6 hp is within the tolerance of the engine spec so some C7 owner without it could still have a stronger car than you. Anyone have a comparison with a C6 on a dyno? Can the dyno even see this "6hp"? This is simply an option for more sound.

Bill Dearborn

You are asking all of the questions that came up on the C6 in 08 when the NPP was offered on the base and Z51 cars for the same price. It quickly became one of the most popular options and people were buying Z06 mufflers with the same valves to update their older cars. The stock NPP was actually louder than the Z06 muffler. You really can't tell how loud a system is going to be when it is idling around town or the engine being winged in neutral. You have to be somewhere where the engine is being held wide open under load to hear the noise. My Z06 exhaust is loud when I hear the the reflected noise off the track guard rail to my left when I pull up the various hills and straights at the Glen. Even with the helmet on and a lot of foam between my ears and the noise it is loud.

I suspect the C7 will be similar to the C4, C5 and C6 and somewhat susceptible to exhaust drone around 1700 rpm under load on the highway. The aftermarket mufflers you mentioned don't dampen the drone and just let your skull vibrate. The NPP shuts the noise down so you can actually hear the radio and don't need a 10K watt amplifier to hear it over the exhaust noise.

Bill

Bill

RMcoolX

Ditto.