The air-cooled combustion engine has a rich history. Initially, liquid-cooled engines were the norm, but air-cooled designs gained popularity due to their simplicity and reliability. The first successful air-cooled engine was developed by German engineer Karl Benz in the late 1800s, then further refined through the 1920s and 1930s. These engines were favored in motorcycles, small vehicles, and aircraft due to their lighter weight and reduced maintenance needs, though liquid cooling eventually became dominant as complexity and horsepower increased.

Notably, the Volkswagen Beetle, introduced in 1938, featured an air-cooled engine, contributing to its widespread success. After World War II, air-cooled engines were used in various small, economical vehicles, including those from Tatra, Fiat, and Citroën. The only US brand to put an air-cooled engine into mass production was the Chevrolet Corvair.

Highlights on view from the Audrain Collections and a few local lenders include a circa 1908 Cameron, 1910 Pierce Four, 1923 Franklin, 1936 Indian, 1956 Volkswagen Beetle, 1961 Chevrolet Corvair, 1968 Tatra, 1969 Moretti, and 1995 Porsche 962, among others.