I think Chris B. brought this up earlier
today. I didn't respond, but you mentioned it, so then couldn't
resist the urge to comment. To refresh everyone's memory,
I have a 20B with a 76" 3-blade constant-speed M/T prop.
So, I can dial in the prop speed desired and the prop controller does
the rest. With it set to 2500 rpm, I'm seeing 7000 engine
rpm on takeoff rolls. (What a sweet sound! It makes those
Lycosaurus' sound like farm tractors.) It will turn about 6700 - 6800
during static runups. But this is a c/s prop, so your
mileage may vary.