Continental IO-550
The Continental IO-550 engine is a large family of fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors. The first IO-550 was delivered in 1983 and the type remains in production. The IOF-550 is an Aerosance FADEC equipped version of the same basic engine, the TSIO-550 is a dual turbocharged version and the TSIOL-550 is a liquid-cooled variant. There is no O-550 engine, which would be a carburetor-equipped variant, hence the base model is the IO-550. This engine family competes with the Lycoming  IO-580 series which are also six-cylinder engines with similar power output and weight. Design and development. The IO-550 family of engines was developed from the IO-520 series, with the stroke increased from 4.00 to 4.25 inches, increasing the displacement to 552 in³ (9.05 l). The engine family covers a power range from to . The engines were first developed in the early 1980s and first certified on a regulatory basis of FAR 33, 1 February 1965 amendment, 33-8, 2 May 1977. The first IO-550 model was certified on 13 October 1983.