If you really want to spin a more scale sized prop, then a reduction drive is in order, and would get you close. The problem is you do not have the room for it if you care about keeping the engine hidden, mostly. Which I assume would be important as well considering the desire for the scale prop.
One of my biggest problems with a scale 3 blader would be the cost. I honestly break too many props to justify the cost. It bothers me enough breaking the $25 ones!
http://www.vogelsang-aeroscale.com/g...eschlundt.html