The Lycoming GSO-580 is a family of eight-cylinder horizontally opposed, supercharged, carburetor-equipped aircraft engines for both airplanes and helicopters, manufactured by Lycoming Engines in the late 1950s and early 1960s.
There is no non-supercharged, non-geared version of the engine, which would have been designated O-580 and therefore the base model is the GSO-580.
All have a displacement of 578 cubic inches (9.47 litres) and the cylinders have air-cooled heads.
Compared to other horizontally opposed engines of similar displacement this family of engines produces high output power by supercharging and high maximum rpm, at the cost of higher weight.
Data from FAA AIRCRAFT ENGINE SPECIFICATION E-285, Revision 2[2] Related lists