How much nitro are you running? Mine ran well on FAI fuel.
I'm using Moki fuel that I can get for $13 a gal. I tried it with and without the cline also have the crankcase pressure. Still just drops off from mid down. I picked up 3 of these over the winter two were in good condition and the other one was gummed up but its good now. Next thing I was going to try was a carb off one of the other engines.