Franklin O-400
The Franklin O-400 was an American air-cooled aircraft engine of the 1940s. The engine was of eight-cylinder, horizontally-opposed layout and displaced. The power output was.
Variants
;8AC-398: at 2,600 rpm.;8ACG-398: at 3,500 rpm. The 8ACG-398 was unusual in using a reduction gearing for take-off and direct drive for cruising.