IS there a kind of a "reccomended running temperature" list for most of the glow engines out there?

I know some engines run hotter than other, and dont seem to mind it.
Like some of the engines boast ceramics. Some have a ringed head.

Just wondering how to decide what temperature the engine should be run at!
If I dont know I usually default to 250.. although it might run a little rich, its better lower than higher!
Thanks
ram

What do you use to measure the head temperature some kind of portable thermocouple or pyrometer? I run all my engines as lean as I can as long as I'm satisfied with the flight. If it loses power on an extended verticle or diving long pass I richen it up a little. Some of these engines like the OS 46FX, ST 45, Rossi 45 Webra's, etc last forever. Sometimes you wish they would pop so you could justify trying/buying something else.

In a normal flight an engine is subject to many different operating temp. Climb out, cruise, high speed pass, low speed pass, low temp on landing approach, add to that nitro %, oil content, choice of plug, needle setting, ambient temp, muffler choice, just set it according to established procedures from experience or manufacturers instructions.

Well sorry I'm still on the floor..
I'm talkin about mostly car engines..
I'm lookin at the .21 Rossi Black magic..
I heard that italian engines run hotter.. so I'm trying to figure out what I should run it at..
I use an IR thermometer.. I point it at the head area and look for the highest temp I can find..
-ram

If it's an abc or abn engine(NON ringed), you want the head temperature to be between 350 and 400 degreesF.
Running a motor of this type exceptionally rich to keep it cooler will accelerate wear. The piston and liner are designed to expand at certain temps to ensure proper fit and compression. If you don't run it hot enough they don't expand and you get the crown of the piston pinched at TDC. This is what you feel when you turn the engine over cold. Ringed engines you can run as rich as you can get away with, and still keep the glow plug lit.
Buggy motors have large heads with alot of cooling fins because they run in a much more air restrictive environment than airplane motors.
But getting an accurate head temp reading is tricky. A temp reading with the engine just idle or even throttled up with no load won't really tell you what it's doing when you're tearing around a parking lot. That's why we set engines a little rich as a safety margin.

between 252-300 degrees is good . 350 watch out.