14x6 too much or too little for OS91surpassII?
a few months ago i asked if my detonation sound was from being too lean with one of my new OS91surpassII's. my tuning at that time and running was with 10% fuel, 14x6 TF power point, and after finding peak i backed off about 400rpm. it had a noticeable rattling (slight detonation), and the suggestions here were to back the needle off some more until the engine is completly broken in..........i did, the rattling stopped, as did power.
today with same fuel and prop, and 2 gallons thru it now, i again peaked the needle and backed off 400rpm......the rattling is back................today was also a day of "let's try different props", so i tried a 12x10...........at the same needle setting the engine runs fine. next flight the needle gets peaked again and then backed off 400rpm...........no rattling or detonation...........and of course the plane (GP Big Stik) is a bit faster.
i have another OS91 in a GP Super Skybolt and it runs identical to this one.
the reason i went with a 14x6 was because of a few reviews of the Skybolt where the authors said they used 14x6's.
is the 14x6 too much or too little prop for the OS 91surpassII?