RE: twin engine size????
The 91 fours strokes would be the most I would put in that airplane. But my choices would be two stroke glow.
I am a sound purest and for the precise reason eveyone always wants fourstrokes (sound) I do not. Fourstokes sound even less like scale than two strokes in my opinion and the point is nothing (At least nothing that I can afford anyway) is going to be even close to the real sound.
The sound of multi two stroke glows is something I truly relish and they always turn heads where the fourstroke may not as much anyway. The sound of my Quad Kaydet with four twentyfives always steals the show and I wont even talk about my Six Pack with 6 twentyfives, A sound you very well may never hear.
So the cleaning choirs I learned long ago to actually relish at the field as enjoyable time to talk with the buds while spending quality time with the airplane and actually accomplish a preflight inspection for the next outing.
I don,t know anything about your english horizontal engine but did watch some the fellows recently fly one and it seems that too may be a resonable engine for your airplane.
If this is your first multi it is likely to be fairly rapid with a higher wing loading So if that is the case then perhaps getting some time in with something like a twinstar would be wise, especially so if you can find someone who understands how to fly a multi on one engine and is capable of buddy boxing you through engine outs via short tanking or a capable radio would be most wise.
Anyway its a wonderful project and I enjoyed the little Urivitch ship.
John[8D]