I can't remember what model # . They came out of Craftsman 2.2 cu.in. saws.

I don't really have an accurate scale here. I'm having them both fitted with electronic ignition, so the magneto is going bye bye. The bare block engine with no carb or muffler weighs about 2.5--3lbs Just a guess by holding it in my hand. The fully assembled engine with steel muffler and magneto weighs a ton. Probably 4.5 pounds.

I have a custom aluminum muffler drawn. I need somebody to build and weld a custom aluminum muffler for me. It's a wrap-around pitts for an inverted mounted engine. It's got a pretty good size expansion chamber and some tubes and baffles inside to try and quiet it down without taking too much power away.

Here is a crude paint image of the plan. Basically, a lot of tubes with holes in them and a few baffles to make the exhaust travel a farther distance before it can get out. I'm hoping it won't be too heavy. Thin walled aluminum should work for most of it. I will only use heavier material around the exhaust flange.