Q102
When setting cruise mixture by EGT, depending on the engine it can be run rich of peak EGT, in which case further leaning results in higher temperatures. Some engines can also be run lean of peak EGT, which is much more economical, in which case further leaning results in lower temperatures.
The question is outdated. Modern engines run lean of peak for best economy, and burning excess fuel is an old-fashioned and expensive way to cool an engine.