A local dealer told me they are made by Corsa. I listened to a car they installed them on, it was a V-6 BTW, and it did sound much better than stock. Reving it up was ok but I didn't get a chance to drive it. My 2007 Corvette, has the Corsa Sports, but it also has long tube headers, cnc'd heads, a racing cam, 410 gears, cai and short throw shifter. That sound is awesome but has the euro sound. I think for the old musclecar sound, I'd look at flowmasters or something similar to them. They would be less expensive and would be easy to install. Hp wise, maybe 5 hp tops over stock. Hope this helps.

 

http://www.youtube.com/watch?v=tgf2FStolDM

http://www.youtube.com/watch?v=1Sf9y...layer_embedded

 

I didn't listen to all of them, but some sounded pretty good, especially the one with headers. Are these all GM kits of a mixture of aftermarket products?

 

all that car has, is the axle back GMPP off road kit

 

Thanks for the reply. The GMPP does sound real nice and is more of the old muscle sound.