AV8TOR,
"I usually just cut the stock muffler apart and gut it. If it is large, I cut it down to size, weld a piece of thin steel over the opening, and weld outlet tube(s) into that."

Why do you cut down the stock muffler expansion chamber? I was under the impression that larger expansion chamber = more power while maintaining silencing capabilities. I know from your posts that you don't mind noise but wouldn't a larger chamber still help with power?

I was under the impression that that was the whole reason not to use the stock saw silencer (other than the small opening) because they are smaller in volume than is ideal. (what is it, something like at least 10 times the cylinder bore is better?). I actually considered using an old muffler from a larger chainsaw, but perhaps that is not the way to go... maybe should go the automotive muffler tubing route. (although I do like the idea of something even lighter like a mousse can or similar, if i can find a way to easily braze/ hard solder it with just a mapp torch.