Originally Posted by dubs1946

Hi Jim i have made a few and i get a good simple muffling effect by running the stinger tubes all the way through to the base of the exhaust box and the tubes inside the box i drill large holes that breaks up the sound wave as it finds its way out.
Personally i would not use scrubbing pads as all exhausts suck and blow and any loose scrubbing metal may get sucked into the engine.
As stated get the main box as big as possible as hot exhaust gasses need somewhere to expand.
Dave.