Allen Aircraft Engine Corp O-675

The Allen Aircraft Engine Co. of Compton, a suburb of Los Angeles California, developed an eight-cylinder horizontally opposed aircraft engine during 1928–1929.

Little is known about this engine, other than that it was never given a Type Certificate and that it was not used on any known aircraft.

O-675
Type: 8-cylinder horizontally opposed
Bore: 4.75 in
Stroke: 4.75 in
Displacement: 673.4 ci
Dry weight: 575 lb
Cooling system: air-cooled
Ignition system: dual ignition
Power output: 200 hp@1800 rpm