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I am interested to know the different ways (techniques) you guys lean for high altitude take offs. I live at the coast and have little opportunity or need for this. Also, at what altitude do you believe it becomes necessary to lean for take off. In case it helps I have a 1967, M20F Executive. Thanks Tony

I fly a M20K 231 with Merlyn intercooler and wastegate making it fly like a 252. We recently had an engine overhaul that caused the TIT to run considerably hotter than on our "old" engine. The "new" engine is in fact the same core, just overhauled to new specifications. The temperature probes are the same as well, so they may be inaccurate, but they should be measuring the relative temperature differences correctly. We had a Mooney Service Center set the fuel flow system at the high and low end per the Continental Service Instruction. This supposedly is very important because an out of whack setup could create many problems. At full power on takeoff (36 inches due to the intercooler), we are seeing 22 gph. That is about 2-4 gph lower than before the overhaul. In cruise (28 inches, 2500 rpm, mixture full rich) we get 15 gph, about 1 gph more than on the old engine. The really concerning thing though is that with the mixture full rich, we see TIT temperatures between 1520 and 1560. We have no ability to decrease that temperature by running significantly rich of peak. On the previous engine with what was probably a poor fuel flow setup, we could cool the TIT to less than 1480 degrees by enrichening the mixture. So my question to the community is 1) should we be concerned with flying the airplane in cruise at 1560 TIT, and 2) should we be concerned that we don't have any "mixture authority" at normal cruise conditions in case CHTs start rising or something like that. The STC that added the intercooler was approved without any change to the performance charts, so we don't know exactly what fuel flow would be expected with certain power settings. If anyone has a copy of a 252 power chart, it would be most appreciated. Thank you.