The problem most likely is you have enough fuel coming into the engine. The problem is these engines are scavanged so well that the fuel may blow thru the engine and not be trapped into the combustion chamber as richly as it should. Thus your oily condition under the plane, granted the engine collects enough heat so that it probably takes having to goose the throttle to get cold fuel into it so it will idle down. Getting rid of the knocks or pings of detonation, is timing problem. My friends in the racing bussiness recommend that you go to a higher octane, or in our case use more nitro content. Also, decompress the engine as much as possible, using head gaskets or short plugs to drop the compression ratio. Lastly, make sure your fuel feeds are unobstructed as possible so the engine doesn't have to starve for fuel and remember most stunt aircraft like Caps, Extras and Edges don't fly around at a million miles an hour. Try different lower pitched props to load the engine correctly and get he desired 3d characteristics you want.
wra