john smith wrote:

How is it that with the same engine, they develop different HP ratings?
R = 160 BHP @ 2400rpm
S = 180 BHP @ 2700rpm
Is there a governor on the R model?


Throttle restriction.

That is *completely* incorrect! As stated earlier, the R model uses a
higher pitched prop to keep maximum RPM's down. Thus the engine is only
able to produce 160hp output.

Happy Flying!
Scott Skylane
N92054