Strato,

Master Airscrew said the maximum safe RPM for their glow G/F props to 160,000/diameter, so a 10" prop is limited to 16,000 RPM; see:

http://www.masterairscrew.com/techbull.asp#C

By all likelihood, at 22,500 RPM, this prop could potentially throw a blade. No one could say it is safe. APC has a 19,000 RPM limit on the same prop size:

http://www.apcprop.com

Two engines made on the same production line, in a CNC process, cannot differ so much from one another. The range of RPM demonstrated on the same prop, can be no more than 300 RPM; between the weakest engine and the strongest.

Making 3.3 TIMES the rated, run-of-the-mill horsepower, is not within the remotest scope. It is like finding a 20' tall man...

Not even a quirk can explain this.

Sincerely,