Silly me, I fogot the paticulars about how I have the engine set up.
1- .250 ventui from Stuka
2- Uniflow metal tank, non pressurised
3- Sig 10%N 20% 1/2 1/2 Lub, boosted to 22% with castor.
4- Supre Tigre style N/V
5- Thunderbolt R/C plug

I get no cosistant runs, it idels at 10, 000 RPM just breaking from 2 to 4 cycle.

Sometime, after a loop the RPM drops and stay so low the plane can barly fly the rest of the flight.
Sometimes she runs a whole tankfull at a wet 2 cycle.
Sometimes it plain stops no matter what the plane is doing, flying level, wing over or loop.
It's driving me more crazier, than my present level of crazyness.
Any suggestion would be appreciated.
Thanks Again, Jerry