In addition to all the great friendships, fun, competition, and burning events, I also like to mess with Muffler design. This will be my 5th design change in 4 years. Last season I got 10's for sound at EVERY event, but lacked power on up lines during the hot humid July/August timeframe. I was using .75 OD aluminum tube for headers and muffler inlet. I thought this was enough, but have never been able to duplicate my 04 design that seemed to provide a "boost" (it was in "Plum Crazy" Staudacher). I went back to that design and realized it had a 7/8 ID inlet tube. Since I was unable to find pre-formed 90 degree radius bends (for my exhaust headers) I went with 1 inch OD X .060 wall 6061 aircraft aluminum. This is SURE to let the engine breath better!! I also had an opportunity to examine the inside of one of Brian Sanick's mufflers when I had the good fortune to help him with a repair - the "diffuser" disc was VERY close to the front end of the stinger chamber and did not touch it at all - it had an .060 gap between a solid disc and the outer muffler tube. I know that weapon silencers use SLOTS for most effective sound abatement, so this time around I'm trying SLOTS around the periphery of the diffuser plate (see picture). The net area of the slots is about 20% less than the 1 inch tubing, but still AS LARGE as the exhaust port cross section on the DA100 heads. All that's left is to try to TIG it all together without blowing any holes in the parts! Can't wait for Spring to try it out! (the dark furry creature is my muffler design advisor, "Binky") The main tube is a "recycle" of the "ring-ding-ding" muffler design flown in 05. No wasted parts in this man's shop! Going to stay with the Aeroworks YAK again this season. I've almost got it trimmed now...
