RE: Great Planes Big Stik 60 tail dragger conversion
When you go with a three blade you're stuck with a limited selection. Here's a comparison of the "load factor" for some available props. The load number comes from ThrustHP. Despite its shortcomings, the load numbers do seem to give a decent indication of whether two props will turn similar rpm on the same engine. As with most things in this hobby you do have to do some experimenting to see what works for you because we all like different things.