The Gnome-Rhône 14N was a 14-cylinder two-row air-cooled radial engine designed and manufactured by Gnome-Rhône just before the start of World War II. A development of the Gnome-Rhône 14K, the 14N was used on several French and even one German aircraft.
The 14K's reliability was poor, so Gnome-Rhône carried out major redesign, using different materials for the pistons and valves, and enlarging the cooling fins to increase surface area by 39%.
The 14N was introduced in 1937 and was quickly installed on several aircraft models. In 1939, minor improvements allowed Gnome-Rhône to increase the compression ratio from 6.1:1 to 6.8:1, which increased power.
The 14N was further developed into the Gnome-Rhône 14R featuring a 2-stage supercharger, but this type was not widely used until after World War II as production of improved engines was restricted by the armistice with Germany.
Data from:Aircraft engines of the World 1945,[1] Aircraft engines of the World 1946[2]