Actual ZL-1 Horsepower.

[Chevy454]

I visit quite a few LS1 sites, and they all seem to rave about the GMMG chambered system. In fact, they're doing a group purchase over at LS1tech right now. Everyone used to want the LoudMouth exhaust, but now everyone seems to be ditching it in favor of the GMMG.

The GMMG chambered is nothing like the restrictive chambered on the first Gens...in fact, when I was replacing the chambered on our '69 I looked into trying to retro-fit the GMMG system.

Are you still running the 10bolt?