Klimov VK-107
The Klimov VK-107 was a V12 liquid-cooled piston aircraft engine used by Soviet aircraft during World War II. It was a major update of the earlier Klimov M-105, adding four valves per cylinder and re-designing several components, allowing take-off power to be raised to 1,600 hp from the 105's 1,100 hp. Although ready for production as early as 1942, the design was not put into widespread use as there was no pressing need for the design until the Germans introduced the Daimler-Benz DB 605 engine in 1943.