Jaka....you might want to check the factory recommendations before you pull
numbers out of the air. My manual states that....
.... 10 or 15% nitro is fine for the engine
....a 16-8 prop for break-in
....and specifically
not to use all synthetic oil in the engine !!
....it gives a specific glow plug recommendation....
not a four stroke plug.
....Voodoo....get some fresh fuel for that engine.
FBD.