There are two strategies for keeping cylinders cool in cruise: push the red mixture knob forward for a rich fuel/air mixture setting that uses unburned fuel to

There are two strategies for keeping cylinders cool in cruise: push the red mixture knob forward for a rich fuel/air mixture setting that uses unburned fuel to lower cylinder head temperatures, or pull the mixture knob out to such a lean setting that an abundance of air and reduction in engine power and heat cools the cylinders. Running aircraft engines “lean of peak” (LOP) typically reduces airspeed about 5 percent in cruise while lowering fuel consumption about 20 percent—but not all engines are capable of LOP operations, and doing it wrong can cause permanent and costly engine damage. source: https://www.aopa.org/news-and-media/all-news/2019/may/flight-training-magazine/technique-lean-of-peak https://www.aopa.org/news-and-media/all-news/2019/may/flight...