I've been posting this over in the extreme speed forum as I consider it an extreme (or at least modestly serious) speed attempt but in the 1/2A category. But since it is 1/2A..
Boomerang lekkie pylon racer
Profi "Rambler" .049 (proto speed, open exhaust)
The prop on it is a 4.1x4.5, I'll be fiddling with sizes along that range.
118 sq in or 108 sq in depending on what you read. Prolly 118.
AUW 9.4-9.5oz, we'll soon see = 11.6 oz/sq ft at 118 squares
I predict it will turn fairly well..
Top speed.. ought to be fun finding out.