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I've got about 65 hours in the Mooney now and I'm starting to notice that it is more difficult to keep the CHT's down, the oil temp down, and the oil pressure up as I fly at higher altitudes. Just wondering if everybody else sees the same thing in their J's. When I fly at 8000' or below, keeping everything where I want it is easy. 65% power, 8.7 GPH (LOP), cowl flaps closed I usually use 2400 RPM. CHT's are usually below 380, oil temp just below 200, and oil pressure around 65 to 70 psi. I usually use WOT unless at lower altitudes. In that case I usually use about 20" MP and LOP. However, when I climb to 10,000' or above that is not the case. The other day we were at 11,500' for a couple hours over northern CA to avoid turbulence. I had to increase RPM to 2600 with WOT and leaned to about 8.6 GPH. That gave me a hottest CHT's between 380 and 390, oil temp about 205 or 210, and oil pressure of about 61 or 62 psi. OAT was about 15C. I had increased the RPM so peak pressure would occur further past TDC to reduce CHT temps. I'm guessing it is because, even though the higher altitude should be cooler air, the indicated airspeed drops off faster than the temperature. Indicated airspeed is a pretty much directly related to air mass flow over the cylinders. So even though the power and true airspeed are about the same, there is less cooling air. That makes the CHT's and oil temp go up. The hotter oil makes the oil pressure lower. Much higher and I might have to pop the cowl flaps open to the trailing position to keep things cool. Agree? Disagree? Bob