Raymrt

I recently bought a 2011 Grand Sport with only 2073 miles on it. I am very pleased with my purchase and want to install a Mild to Wild wireless unit in it. I have one question, not being familiar with the different exhaust systems on the Grand Sport. There are NO visible actuators sitting on top of tailpipes. There are NO visible valves in any of the four tailpipes. At about 3500 rpms there is definitely a noticeable drop in pitch and an increased tough sound. How would a Mild to Wild function on my Vette? Is it even doable.

RicK T

If your tail pipes don't look like this, you don't have NPP:

icntdrv55

Also, you can verify if the car was equipped with that option from the factory by looking at your RPO sticker in the glove box. Should have the option code NPP listed alphabetically if it was OEM.

Homer3D

Take a picture of your exhaust and we should be able to tell you if you have NPP installed. Other option is to look for the NPP RPO code as suggested by icntdrv55.

If you have a stock non-NPP exhaust, you might want to look at the "Stock Muffler Mod" to add more sound. Search and you should be able to find it.

Raymrt

My Vette's tailpipes do not have the two actuators on them as in your photo. I'm new to the fourm and have not figured out how to attach a Photo to a "reply" post. I guess I don't have nnp then. By the way, what does nnp stand for?

Homer3D

NPP is the RPO code for the dual mode exhaust. I am not really sure if the letters actually stand for anything.