IMO the loudmouth sounds like ***. The GMMG has a true musclecar sound. There is no comparison between the GMMG and the loudmouth. It's worth every penny.

 

And I picked up 25rwhp & 22rwtq with ONLY a Direct-Flo lid and GMMG cat-back on my entirely bone stock 2002 Z28. Both dyno's were done at the same place and the #'s are SAE corrected.

Obviously, the GMMG is most-likely good for about half of what that combo gained my car.

Mike