It is winter.

Low 60's, cloudy and a little wind.
I changed the venturi in the Ringmaster 576 engine to one from a .25. It and the OS needle valve asm. work very well on the .40/.46 engines. I also removed the spinner and put the heavy hub on. In case the spinner was getting in the way of the air flow. Then on a whim I tried a higher nitro fuel. It worked. 3 flights with perfect engine runs. I tried a tank of the regular fuel and it acted up. For some reason the engine in the Ringmaster needs higher nitro but runs fine on low nitro in other planes.