Manual NPP

NPP is the RPO code from GM for the dual mode exhaust on a sixth generation Corvette.

There are butterfly valves in the mufflers that, in stock form, open at about 3,000 rpm allowing the exhaust to bypass the muffler.

This gives a small horsepower boost over the base exhaust, six horsepower.

With the valves closed it's as loud as a Cadillac.

I thought this was a performance car!

So I put a push switch in my dead pedal.




Now you can hear the 436hp of American Canadian LS3 at idle!