Mitsubishi Kasei MK4B 11

General characteristics
- Bore: 150 millimetres (5.906 in)
- Stroke: 170 millimetres (6.693 in)
- Displacement: 42 L (2,567 cu in)
- Diameter: 1,322 millimetres (52.05 in)
- Dry weight: 780 kilograms (1,719.6 lb)

Components
- Reduction gear: Double planetary spur reduction gear, Ratio: 0.538:1

Performance
- Power output:
-- 1,850 horsepower (1,380 kW) at Takeoff
-- 1,680 horsepower (1,250 kW) at 6,889 feet (2,100 m) Low blower rated with water injection)
-- 1,570 horsepower (1,170 kW) at 18,044 feet (5,500 m), Rated high blower with water injection)

Design/Development
Although originally ordered by Imperial Japanese Navy, the Kasei was based on the earlier Mitsubishi Kinsei engine, itself based originally on a Pratt and Whitney design. Produced in a wide variety of models, the Kasei began with a rated power of 1,530 horsepower (1,140 kW), with a gradual evolution to 1,850 horsepower (1,380 kW) in later wartime versions. Three variants were developed for the Japanese Navy starting in 1939. It was also later adopted by the Imperial Japanese Army as the Ha-32 engine, and was developed further into four variants, including the Ha-111. Production was 8,596 units of all variants.

Physically, the engine had a rather large 1,322 millimetres (52.0 in) diameter compared to the 1,180 millimetres (46.5 in) of the Nakajima Homare engine. Its size and weight meant it was a challenging engine to use on single engine fighters.

Variants
- MK4A 11 - 1,530 horsepower (1,140 kW)
- MK4B 12 - 1,530 horsepower (1,140 kW)
- MK4E 15 - 1,530 horsepower (1,140 kW) - Same power as the MK4A 11 with
   improved altitude performance
- MK4V 27 - 1,795 horsepower (1,339 kW)
- MK4R-C 23c - 1,820 horsepower (1,360 kW) - Fitted with a turbo charger that
   allowed an output of 1,420 horsepower (1,060 kW) to be maintained up to 30,000 feet
   (9,144 m) instead of only 15,750 feet (4,801 m)
- MK4U-4 26a - 1,820 horsepower (1,360 kW)- Mechanically-driven 3-speed
   supercharger
- MK4G 25 - 1,825 horsepower (1,361 kW),1,850 horsepower (1,380 kW)
- MK4P 21 - 1,850 horsepower (1,380 kW)

Applications

- Kawanishi E15K "Norm" - Kawanishi H6K "Mavis" - Kawanishi N1K-J "George" - Mitsubishi G4M "Betty"

- Mitsubishi J2M "Jack" - Nakajima B6N - Yokosuka P1Y "Francis"