Bandangle
What is the diameter of the 87 inch cowl? Looking at the full size photos that Maxam provided, indicates that the engine should be a bit larger in diameter than the fuselage. If it can be reliably shown that the 7-77 will fly a 30+ pound airplane with reaonable authority the 87 inch version may indeed be the way to go if the engine looks right on that size model. I really want to build a Stearman without a cowl and without a dummy engine, but if I am going to spend that much for an engine it has to look right. The BUSA 1/3 scale Stearman flies great on a five cylinder Moki and sounds very realistic but it isn't SCALE.