thats the kind of information I am looking for, thanks so much. Great forum.

I fly a sig something extra (40 size) with a Magnum 91 4s (13x8). It flies at 6 lbs and gives me full vertical anything.

Yes, I am from the school of math that clearly defines 90 size 4 strokes fit into 40 size airplanes.

Starting to look like it will be a YS 91 for the 60 size staudacher. My math says 120 size, but not my wallet........Then that darned weight thing again.

Thanks for your help......