The merge muffler was developed under the same principles as the merge collector and the Y-pipe. The two 3-1/2" inlets come together with a smooth transition to balance exhaust pulses. The muffler core placement takes advantage of the sound cancellation at the most active point of the exhaust system. The core of the muffler is actually tapered to expand out to a 5" diameter at the exit and improve the scavenge of the system. It has a 7" case and at only 29" total length takes up less room and weighs less than a Y-pipe muffler combination.