Ah but check out the cruise settings for the Favoris. Max torque is at 2400 engine rpm which gives 1280 prop rpm, for a cruise at 200 kph.
Take off engine rpm is 5000 which gives 2600 prop rpm, and t/off roll of 350m. Not an impressive rate of climb however at only 550 ft.min; I should have thought a turbo diesel might have been a better engine choice.
Also I wonder how a car engine copes with regular thrashings at 5000 rpm for take off?