Continental Motors started producing engines in 1905 and a radial aircraft engine was made in 1929. Production included automobiles, and engines for other manufacturers. They also produced gasoline and diesel engines for battle tanks in the 1950s.
Continental started producing their well known 4-cylinder opposed aircraft engines in the 1930s, followed by 6-cylinder engines after World War 2. In 1947, Continental introduced the E165 and E185, both 471 cubic inch displacement flat-six piston engines. A later development, the E225, was able to produce 225 hp. Civilian manufacturers adopted the military system of engine designation and this engine became known as the O-470 (opposed cylinders, 470 cubic inch displacement).
Aircraft that use the O-470: Beech Bonanza, Beech Baron, Beech T-34, Cessna 180, 210, 310, North American Navion, Dornier Do 27, Bellanca Cruisemaster and many others.