G38 with a very small B&B muffler on 40:1,

prop, 3W 19x8

RPM, 7550

a lager muffler would probably help give a few more RPMs,, the plane weighed about 16 pounds and the motor pulled it rather well, the plane is a old thimer racing plane so it has a thinner racing wing,,

see the plane here,,
http://www.fly-imaa.org/imaa/hfartic.../v12-2-34.html

Jim