I'm in the process of setting up an engine temperature telemetry sensor in an Extra 300 that will be powered with an O.S. 81a 4 cycle engine. Any idea of the temperatures that I will encounter at the cylinder head, header pipe, or muffler? Any help would be appreciated. I'm trying to establish threshold settings of the sensor, and to learn what possible temperatures to expect.
Karl

So many variables effect the temperature and all the places you mentioned will be different. The only objective way to establish that would be to find a fellow owner with the same engine running the same prop, on the same plane, same exact fuel, same glow plug and the same ambient temperature.

Just be sure that you have enough air flow, be sure the exhaust area is at least twice the outgoing area, baffle the engine so that the air must go though the fins. You won't need to worry about temps and you only have to make sure the engine is rich enough that it gets oil. These engines can be converted to gas and as such will run much hotter so it is not about getting the metal to hot. It is about lubrication and smooth running. Don't bother with your telemetry. Get an altitude and airspeed sensor instead.

Karl, tell us more. Is this part of a commercial telemetry package, or just your own temperature measuring setup?

I received a 14sg for Christmas, a very welcomed gift after using a 7uap for almost 20 years. The new radio has many new features, including telemetry. It sure is nice having the receiver voltage displayed while flying. Having the capability for various sensors, I decided to add a temperature sensor to monitor the engine temp on my cowled 4 stroke aerobatic plane. I'll be able to see the effects of cowl baffling, as well as venting. I'm simply using the provided technology the radio gives me It's quite a radio, and I have at least 3 months to figure it out since it's winter here in Michigan. I'm expecting the engine head temps to run in the 300-350F range.
Many thanks to all that have responed.
Karl

Got Extra?

That sounds like a nice system. Would like to see it in the air.