Has anyone run the GGB with big HP? what did they do to the EGTs? and performance.

zt260 is pushing over 1300 h.p. with that set-up.

I'm talking 1500,

Check, do you monitor your egts? what temps are you seeing at wide open throttle?

This is my 3rd set of GGB, custom ordered mufflers, to fit my application. They were ordered January 2005, 6.5" Outside diameter, with a full 4.5 straight through Inside diameter. I received them June 6th 2005. How do you think they will work?

Mine have a a large cutout in the bottom to get more air flow. I have not lost any power.

BTW mine are the same size.

I just got two sets of gill mufflers for my boat one full time slip on's and the select sound clamp on's. The full time looks a little restrictive have not used them yet. I plan on running the select sounds once I find some linear actuator so I have full range adjustment of open to close. E-bay deal $50.00 per set becouse I have 3.5" pipes for my sbc with dry gill manafoilds.

One more of the select sound muffler.

The first set I was sent were gutted for some good dyno numbers, the boat was louder with them on. The second set sent the EGTs over 1500 degrees by 5000 rpm. The third set does not impress me. Actually they are quite a let down after waiting for 6 months. When I asked Graham if I had to go somewhere else to get mufflers that would work, his reply and I quote " GUESS SO!"

GPM,

You could always switch from the blower to a turbo and have a built in muffler and still easily make that HP!! Just kidding.
I honestly wouldn't expect the manufacturers to have a product for your application just yet. They are still trying to get the merc stock stuff legal w/o HP loss!! I have some clamp on GGB's on order. Hopefully they don't kill my power too bad.

Craig