Hello,

I have a World Model Super Chipmunk 90s ( Flaps and Retracts) going to be powered by an OS 91 Four Stroke with the Pump. I am trying to figure out what prop size would be best for speed and/or as much speed I can get from the .91 FS and best prop for the *Plane*.

Is a 13X10 size too small for this plane? Or is this fine?

another prop is a 14x8 or 14x10?

Please advise.
(It would help if you have or had this size engine and a pretty close setup)


Thank you very Much