Well the OS .65AX is tuned to turn larger propellers. So it ought to be fine. It now tends to act more similar to a four stroke engine. When you looks at the suggested props they do suggest some fairly big props for it.
The Saito 82 engine is actually smaller than the Saito 100, 115 and 125 engines are. So it probably just fits inside the engine area. Same for the OS .81 engine too, which probably fits a little better since the plane was made for Hangar 9 and Tower Hobbies.
Last edited by earlwb; 03-17-2014 at 07:31 AM.
Reason: add more info