My engine doesn't really come alive until I see temps of 245-250. Don't be afraid to turn the happy screw in to make it run.....just make sure you've still got smoke.

I've tested with OS P3/P4s and O'Donnell 97Ts. The best fuel economy came from the P4, but it could make the tuning window pretty narrow. I ran the 97T at Nats and a state series race last weekend and the plug worked very well. That plug will give you slightly better fuel economy than the P3 according to my testing.

I've been kind of rough with my engine. My engine came off the track at Nats around 300 degrees, and the air filters were clogging in the space of 10 minutes at the track I was at last weekend. My engine's still got very good compression at around 1.5 gallons on it, and the bearings still feel smooth. My air filter clogged so bad in the main last weekend that the engine ran extremely rich for the last 15 minutes of the main. It kept running though! Pretty amazing little mill!