We have a Maxprop. PYC has always touted that the Maxprop has the same efficiency in reverse because the blades rotate putting the same edge forward in either direction. Playing around with that along with what 'CCA boater' posted on windage is a place to start.

For a while I thought about making a scale. All that would be needed is a 2" stainless tube with a spring in it. ( our Garhauer rigid vang is basically that. ) Make the tube, put a spring in it and have a fixed hook at one end of the tube and a hook on the spring on the other. The harder the pull the more compact the spring becomes (like a fish scale). Then it's just a matter of hanging weights on it to see just how far it compacts with different weights.