I've got a Testors Series 21 McCoy .40 Black Head engine that I plan to put in a 42 inches (1067 mm) wingspan Sterling Kit S-46 Profile Hellcat. It has about the same proportions as the Sterling S-1 Ringmaster. I had a spare YS muffler, so I did a few modifications to make it work for the engine.
Attached are photos of my modifications. The only thing lacking is JB Weld epoxy filling of the original engine mount holes. Although I don't have a weight scale, the muffler seems to be about the same weight as the Tatone Peace Pipe muffler I was going to use.
With the muffler's larger chamber, I'm thinking that it shouldn't slow it down or overheat it. Most of the time, manufacturers put on compact mufflers, because they are easy to pack in the box and cheaper to make. The slightly narrower muffler inlet is about the width of the cylinder sleeve. On other engines like OS and Enya, the side of the exhaust outlet contains the mounting bolt area. The muffler inlet height is slightly greater than the McCoy's exhaust outlet.
I'll know more, when I test the engine, but I'm just wondering what you folks think.
