Reply to "GTS exhaust gutting"

John, my modification is hard to explain. all I did was cut some holes in various places. With a good high resoultion pic of the inside of a muffler, I could mark out what I did. I was a dumb a$$ for not taking pictures. I really didnt remove much but opened up some passages to try and make the dampening chambers work without restriction. I will try and describe.

The two baffle plates have an area with about 8 3/8 holes on each side. I cut out these 3 areas in a circle to make about a 2 inch hole in each side of each baffle. Two front and one rear. The second rear baffle area I cut a half moon hole. This was in hopes of prevent resonance between the two tips by change the tuning frequency on each side of the muffler. These cuts will help air flow out better from between the baffles.

The second modification involves cutting two 1 by 2 inch slots in the perferated pipe on the inlet. Between the two baffles I cut one of these rectangular holes on each side. These holes should reduce the back pressure wave from reflecting back up the inlet from the end of the muffler and allow additional flow.

On the 4,6 this modified muffler was amazingly quiet.