EGT and CHT Readings for flight above 12,000 fet

[Peter Soderquist]

What EGT and CHT readings should I be looking for at 12,000 to 15,000 feet? And, at these readings, what kind of fuel flow should I expect?

Thanks.

Peter

[Dave Fitzgerald]

Peter

What are you flying, a single, a twin, turbo or non turbo? Turbo normalized planes will run hotter at altitude because of producing more power in thinner air and the heated air from the turbo. I fly a PA 39 turbo and at 15000 and about 65 to 70% power the number 4 cylinder will run around 400 with exhaust gas temperatures around 1340 to 1380. The other three cylinder head temps will run around 330 to 350. The number 4 cylinder runs hotter because the oil cooler sets right behind it.
EGT and CYL temps will vary depending on how much fuel your burning. At 15000 and 24 square, I burn about 9.2 to 9.5 a side. I know some pilots will lean a little more than I do but I've had to change too many cylinders in the last ten years from leaning too much. Even with the high price of fuel it's still cheaper than cylinders.

[9089P]

Hi Peter,

In case you fly a single, I fly a 260B and lean to keep the egt below 1400 on mine which is roughly 100 rich of peak. In cruise the cht runs in the 340's and I only monitor it during climb to keep it below 400 which is not a problem. At 12500 I'm in the 10-11 gph range.

Good luck, Don

[Peter Soderquist]

Sorry. I forgot to mention I fly a 260B.

Thanks for the responses.

[N8632Y]

[Bernie Mazurek]

[N8632Y]

I think the goal of running your engines is to get them to the temps that are the healthiest for them. Too cold, too hot, not good.
So most times when I fly, my settings depend on the mission, time of year, altitude, OAT.
Lycoming's fuel, EGT, CHT graph clearly shows that 100 ROP gives best power, while 50 ROP gives you the hottest CHT, which might be of help when it's below freezing and your CHTs are way to low and the oil is still solid.
OR in the hot humid summer your temps are the same at 150 ROP and at peak or slightly less, since peak is when the first cylinder peaks, the others are in the hotter zone, so summertime climbouts are much richer.
Bottom line is get your CHTs to their happy temps. Just thoughts.
Most types of engines like to be run, look at the breakin schedules.

steve