im changing my 2.50'' ex to 3'' from x-pipe which is 3'' to tailpipes, now im using 2 chamber flows 40 series and have 50 series 3 chamber 3'' flows but are way to big for the 69mach1, compared to the 40 series they are long, whats a good 3'' muffler that flows good and are the same size as the 2 chamber flowmaster, need to have a little less noise because this thing is loud, 408w 69 mach1.