R-1830 was first run in 1932

R-2000 production numbers for 1941 are 9 engines, 1 in July and 8 in December. For 1942 406 engines are produced followed by 1449 in 1943 and 3164 in 1944.

Specifications (R-1830-S1C-G)
General characteristics

* Type: Fourteen-cylinder two-row supercharged air-cooled radial engine
* Bore: 5.5 in (139.7 mm)
* Stroke: 5.5 in (139.7 mm)
* Displacement: 1,829.4 in³ (30 l)
* Length: 59.06 in (1,500 mm)
* Diameter: 48.03 in (1,220 mm)
* Dry weight: 1,250 lb (567 kg)

Specifications (R-2000-3)
General characteristics

* Type: Twin-row radial engine, 14 cylinder
* Bore: 5.75 in (146 mm)
* Stroke: 5.5 in (139.7 mm)
* Displacement: 2,004 cu in (32.8 L)
* Length: 61.02″ (1550 mm)
* Diameter: 49.49″ (1257 mm)
* Dry weight: 1,570 lb (713.6 kg)