britbrat,
Dont get me wrong because the idea of removing the baffle is often good for better breathing and more power. The pipes I have suggested are modern flatdisk "fourchamber" pipes, "Hatori look a like" but much cheaper. They have one expansion chamber and three silencer chambers. Thats why they are more guiet than any other "bolt on" muffler and give your engine the supercharging effect you desire. The modern OS mufflers has one expansion chamber and only one silencer chamber.