Last weekend, I finally ran up the G38 in the Papsi Chipmunk.
As I had made some modifications to the mufflers (see previous post), I wasn't sure what power or noise output I would get.

The mufflers consist of the stock can muffler with a short piece of 5/8" pipe brazer to the bottom, angling backwards and a briggs and stratton lawn mower muffler brazed on as a secondary muffler.

This combination proved great. The engine runs relatively quiet but still retains the deep "throaty" sound.

I ran a 20x10 prop and after two tanks or to, I got over 7000RPM and idle was only 1500 RMP or so. Most impressed.

After slightly richening the low end, I got smooth transition from low to high.

Not many excuses not to fly the plane now