First starts - clipped combat prop 4.5x2.75 - too much shaft load I think, can't get it past overrich low speed or starving for fuel.
Just returned from the basement - now it's 3.8x2.75 (and carefully balanced).
I am not really sure how to mentally equate 1 blade to 2 blade shaft loads. These would normally run a SB 2.875 x 4.0-4.5 or so, that means it scribes a 5.25 diameter circle.