Cheers Bax, Running with that prop and 5% nitro 18% oil fuel she is getting quite hot inside that Christen eagles cowling. Performance is not affected by this heat, but she does seem to be a tad hotter than what I'd consider as normal. There is more than enough cooling and exit area heat escape. Would a switch to say 10% nitro and 20% oil help cool her down.
I'm richening up by around 200 rpm from peak to 6800, is that about right or do I need some more. I believe the engine has only been flown 8 to 10 times from new.
Would a Graupner G-sonic 20 x 8 spinning at 7800 on the ground be a little under propped then.
Cheers

James