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I have a Continental C-90 on my 750, I’ve used 2 props, and both are good. First one is a Whirlwind ground-adjustable 72” two blade, Second one is a Catto fixed pitch 76 x 37. The Catto allows for a maximum of 2630 RPM in straight & level flight, which is the top limit for a max of 5 minutes on the C-90. Of course, with the Whirlwind you can adjust it to make any RPM you want. I usually ran the Whirlwind pitched to get the same maximum range of 2630 RPM.
Having flown with both props somewhere over 350 hours each, my experience shows the Catto 76” is the better climb prop, but not by a huge amount. I did raise my nose with a custom fork to allow for more clearance with the Catto. The advantage of the Whirlwind is of course it’s adjustability. I would change the pitch in the cool winter months to get more bite and a little better top end speed, but keep in mind it’s a high-drag, slow plane anyway. In summary, I’m happy with both of them.