RE: .60 engine in a .60 warbird?
I think the H9 P40 deserves a nice four stroke. There are some very capable four strokes that are inexpensive. Magnum 91 and THunder Tiger 91 are both good and should do weel in the P40. Normally prices from Tower for these are about $180. The Magnum goes on sale once in while for about $149. At this price I see no justifiable reason to buy a two stroke.