Nosedragger, thanks for the info on the ignition timing, I need to do a bit more fine tuning, I've just been running this engine in, after this last weekend it has had about a dozen flights and seem to be freeing up nicely. With larger props I did notice a top end miss sometimes and suspected over advance.
I would be interested to talk to the cam guy as I think that the biggest improvement will come from this area. Can you please pass on his details.
I dont ever expect to get the performance of a good 2 stroke but the way it idles, starts and the fact that there is never any oily residue on the aircraft make it a winner for me.