Thermodynamics state that the otto cycle is significantly more efficient if you can raise the temperature differential between the incoming air and the combustion chamber temperature. You can't really lower the temperature of the air much but you can raise the combustion chamber temperature as much as practical. That's why most new cars run 195 degree thermostats. Older cars didn't because of the limits of coolants of the day like alcohol and early glycols. They evaporated at high temperatures.

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A lone amateur built the Ark. A large group of professionals built the Titanic.