Not sure I understand. Did you completely cut away the baffles on the cover plate and also open up the rectangular area that has the holes in it on the front side of the muffler? I was thinking more along the lines of drilling larger holes to increase air flow and prying the baffles open a bit more. I'll just play it by ear (so to speak).I folded open the front cover and removed the baffles. Drilled out opening behind the outlet cover. It is a little loud now. May want to try leaving baffles and try just opening the outlet.