RE: Everything Radial Engines
I believe there are a few decent reasons for using methanol over gas. One is the availability or lack there of of carburators. Walboro is the most common Mfg for small gas engines. Getting one to fit the needs of a designed engine is not so easy as it may sound. Especially if the engines are in the low volume of production nunbers.
The other is power. Meth produces more power than gas. So you can have the same sized engine that produces more Hp. A decent consideration until you get into the larger engines.
One last consideration.. space and efficiency. Long stroke, low rpm engines take up room. Cowl size even at 1/4 scale can be about 10 inches i diameter.. not so big. Secondly prop efficiency. A low rpm prop, while seemingly ideal just doens't produce the power as the full sized one. So you need more rpms.. its just the way it is.