RE: Engine and position on a U-can-do 60?
cafusin
I have UCD .46 with an inverted Saito 100 and a P-51 with a Saito 100 inverted and no problems with starting or running. I have a friend that has a inverted OS .91 2 stroke in a .90 UCD and that engine starts easy and runs well, and I have no reservations about inverting the engine in my next plane if the situation calls for it. I have no experience with pumps so I can't help you there.
\K.O.