sorry for the edit !

I don't think 8800 is over Revving a 180 4St Glow engine, then again I think 8000 is a bit low, but that is just my opinion, so I could be wrong,, if some one is up around 10,000 with 10% Nitro then I would agree they are not efficient.

when I researched cams for my friend's 400 Chevy (460HP) I read that an engine's Peak Torque Point is where the engine's Power is most "efficient", yet with that I also read that a racer can benefit if he over Rev's his Peak Torque Point by 200 to 400 RPM (BTW, Mr, Isky said that)

if you go and look on the Tach Reading page you will see some guys where using a Wood Prop that loads more than the APC 17X8w, yet they were Revving their Saito 180s close to what my engine was with the APC, yet some were Revving higher than my magnum would,,, so in my opinion I do not think 8800 is over revving a Satio 180,, plus, Saito gives Prop Size/RPM numbers

example, look at my Magnum 180 4St Static Numbers

APC 17X8w 8800
Xoar 17X8 8200

Note that in flight the APC accelerated my plane faster as well as producing a faster top speed, therefor I knew my engine was over Propped with the Xoar, and the engine's Peak Torque Point was somewhere between 8200 and 8800

but like I said LOL just my opinion I could be wrong

Jim