My gasser runs about 209 degrees F. That temp was taken off the head, just after landing from a 15 minute flight. My understanding is most people with gassers like to stay under 200 if possible. Anywhere from 165 to 180. An ABC glow motor needs to be warm. They should be running about 350 degrees F. at the head when tuned properly. Any cooler and the liner can pinch the crown of the piston, robbing power in the long run. Ringed glow motors can run much cooler since there's no pinch at TDC to worry about.