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            Scott,
        Regarding cooling magnetos:  I was asking myself the same question a     few months ago.  First I called up Unison to get operating     temperatures for the Slick Mags on my O360A1A.  Normal operating range     is 180-210 deg F measured on the case in the coil location.  I then     epoxied a thermo couple to the left mag and place two more     thermocouples 1/4 inch off both mags to measure local air     temperatures.  With the readouts in the right seat I went flying.      OATs were in the 70-80 F range.  I was suprised at how low the     temperatures were.  Steady state was reached at about 130 F. The air     temperature consistently lagged the magneto temperature by 10 F.  I     continued with landings and taxiing back for take off.  I figured the     lack of air flow might bring the temperatures up.  It did, but not     very much.  The highest temperature measured was 170 F.
    As a result of these measurements I have elected to skip magneto     cooling.  I will repeat these measurements once our local temperature     hits 100 deg F this summer to make sure recommended operating     temperatures are still not being exceeded.
    I have the long engine mount, a carburated O360, and my oil cooler     exhausts into the engine compartment in front of the #2 cylinder.  The     air behind the engine must really be whipping around, because it is     doing a great job cooling the mags.
        Chris Zavatson
    N91CZ