I never said 200 to 240, it's always been 200 to 220 with 240 being the upper limit. You'll get better power at 240 but you'll find at that temp your .37 will start surging and your tail will start swinging out. The best way to check the temp is with a calibrated IR temp gun at the back of the cylinder and head.
OleC, try setting your engine this way you will like it set using these temps as a guideline.
Here's the info from post #2 again...
ORIGINAL: evan-RCU
All model airplane engines are the same 200-220 with 240 and up too lean and below 200 too rich. Check on the back of the cylinder with a IR temp gun or use spit, does nothing too rich, bubbles just right, boils off fast or "jumps" off too lean. All in degrees F, sorry...