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I've been on here quite a bit looking for a solution to the high CHT problem with my C. A related problem was leaning. Sometimes I couldn't get below 11 gph and EGT's were all over the place. CHT's were also all over the place with the front cylinders up to 60 degrees cooler than the rear, or specifically #4. I've been told C's just run hot. I used up a tube of RTV plugging every hole, seam, etc in the baffling. It was suggested the the carburetor might be wrong or need overhauling. I even thought I should switch the O360 out for an IO360 to be rid of the carburetor. I've experimented with all types of power settings and mixture settings. The only thing that seemed to help at all, was to reduce prop RPM as early as possible and as low as possible. And I'd never been able to close the cowl flaps without raising the CHT's too high. The solution I recently discovered is throttle position. At WOT and Full Rich mixture, everything is fine. But as the mixture is pulled back, the CHT's would go way too high, and I know the engine's not meant to be run full rich at say, 6000 ft. Solution: Prior to pulling the mixture back, pull the throttle back just until the MP needle moves 1/2", then push the throttle back in just enough to get the 1/2" back. Leave the throttle there and adjust mixture as required the rest of the flight. Now I can leave the Prop RPM high or at least around 2500 throughout the climb. CHT and EGT's are all much closer between cylinders now, and CHT's are lower across the board. I've tested this on four different 1.5 hour flights and two 4+ hour flights with excellent results. It's been said on this board before, that WOT with the O360 carburetor opens an additional port or jet dumping extra fuel. It seemed counter intuitive to me to reduce that extra fuel as a means of reducing CHT. And I'd tried pulling the throttle back just a bit, but it obviously wasn't enough. I have to pull it back enough to reduce MP and then put it back just enough to get the MP back. So now I'm speculating that the extra fuel works fine at full rich mixture, but when leaning, it's somehow messing with the distribution of fuel, and putting some cylinders too rich and others too lean. This picture is at 12,500 nicely LOP and running smooth as butter. I neglected to get a picture of the CHT/EGT screen but will do that on the next flight.