If you’re really interested in getting optimal performance from your engine, only fly aircraft with an all-cylinder monitor (after you’ve read and absorbed the content of all of John Deakin’s articles that Centaurus has conveniently linked for us). I lean during the climb to maintain the ‘balls to the wall’ sea level EGT on my hottest cylinder. With the fuel system and timing set up properly, all CHTs remain (and can be seen on the monitor to remain) below my ‘caution’ temperature of 200c.
Interestingly, the ‘steam driven’ original single point CHT gauge rarely reaches the bottom of the green arc, much less get anywhere redline. I reckon I’d have to get the cylinders to melting point before that gauge would redline.