Lycoming O-340

O-340
Type	Piston aero-engine
Manufacturer	Lycoming Engines
First run	1954
Major applications	TEMCO-Riley D-16A Twin Navion Brantly B-2

The Lycoming O-340 is a family of four-cylinder horizontally opposed, carburetor-equipped aircraft engines, that was manufactured by Lycoming Engines in the mid-1950s.

The O-340 was designed by Lycoming specifically for the TEMCO-Riley D-16A Twin Navion project. Jack Riley, the designer of that aircraft was interested in an upgraded version of the Lycoming O-320 that would produce more power to give the Twin Navion a better single-engine service ceiling. The Lycoming O-360 was still years away in development and so a modification of the O-320 was undertaken by Lycoming. The O-320 received longer cylinder barrels and a crankshaft with a longer stroke to increase displacement and different piston connecting rods. This increased the compression to 8.5:1 and boosted power output to 170 hp (127 kW) over the O-320's 150 hp (112 kW). The engine was later used in a number of airplanes and helicopters and also in amateur-built aircraft designs.

The O-340 family of engines covers a range from 160 hp (119 kW) to 170 hp (127 kW). All have a displacement of 340.4 cubic inches (5.58 litres) and the cylinders have air-cooled heads.

The O-340 series was certified under Type Certificate E-277 and first approved on 20 July 1954. The engines are approved for both tractor and pusher applications.

Data from TYPE CERTIFICATE DATA SHEET NO. E-277, Revision 5

...
Wikipedia