For the Nay Sayers and the merely impatient, RPM figures from our static tests. Remember, this had an ES pipe on it. The SAP 180 was brand new, right off the production line:

APC 17x12 Std blade: 8200 RPM 19.5 lbs static thrust
APC 18.1x10 Std blade: 7700 RPM 20.5 lbs static thrust
APC 18.1x10 wide: 7400 RPM 20.4 lbs static thrust
APC 19x11 Std blade: 6400 RPM 19 lbs static thrust (Proved what we expected -way too much prop!)
APC 15.75x10 3 blade 8200 RPM 21 lbs static thrust (Prop is a re-pitched "Lockhart special")
APC 17x10 Std blade 8900 RPM 22.3 lbs static thrust (Not enough prop, obviously)
Vess 18x6 wood prop 9300 RPM 26 lbs static thrust (Yep, not a pattern prop)