Well, I guess the muffler I cobbled up is pretty efficient on my modified 23.6cc Kioritz. Today, just for grins, I ran it without the muffler to see if/how much rpm's it might gain. It gained maybe 50 rpm's!! I was pretty surprised. The muffler is the stocker, cut about in half just below the port hole. I took out all the baffling, then welded a flat plate across the opening. I then drilled two holes, and brazed in two 7/16" i.d. brass tubes about 5" long each. I made them that long to get them to exit below the low wing, so that any "glop" would not get on the airplane. The only complaint I have is that the seams of the muffler leak a bit, and I still get just a little bit of crap on the plane. I'm fixing that little problem right now! It weighs 6 oz., which seems a little hefty though. Someday I'll get a tig welder and be able to play with aluminum! What do the aluminum store bought mufflers you guys use weigh?

I don't know why I'm still searching for more performance, as this thing flies just great, and most flying is done at half throttle. It's just my nature to keep looking for more power I guess. I do it with everything I own; hence my motto below!

AV8TOR