Alfa Romeo 121

The Alfa Romeo 121 was an eight-cylinder, air-cooled, inverted V engine for aircraft use produced in Italy. It was typically rated at 280 kW (380 hp).

Applications

• Ambrosini S.7

Specifications

Data from Jane's All The World's Aircraft 1953-54 ^[1]

General characteristics

• Type: Eight-cylinder inverted V-8 air-cooled engine
• Bore: 120 mm (4.72 in)
• Stroke: 110 mm (4.33 in)
• Displacement: 9.9952 L (609.9 in³)
• Length: 1,780 mm (70 in)
• Width: 684 mm (26.9 in)
• Height: 700 mm (27.5 in)
• Dry weight: 345 kg (760 lb)

Components

• Supercharger: Centrifugal type
• Fuel system: Two horizontal carburettors, or one injection carburettor
• Fuel type: 100/130 grade fuel
• Oil system: Pressure type.One pressure and three scavenge pumps
• Cooling system: Air cooling
• Reduction gear: Spur gear type: reduction ratio 0.621:1

Performance

• Power output: 284 kW (400 hp) at 3,000 rpm (take-off), 246kW (330 hp) at 3,000 rpm (max continuous power)
• Compression ratio: 6.5:1
• Specific fuel consumption: 290 g/hp/hr (0.63 lb/hp/hr) (take-off),
• Oil consumption: 2.5 kg/hr (5.5 lb/hr)
• Power-to-weight ratio: 0.82 kg/kW (0.53 hp/lb)

References

• Bridgman, Leonard (ed.) (1953). Jane's All The World's Aircraft 1953-54. London: Jane's. 
• Gunston, Bill (1986). World Encyclopedia of Aero Engines. Wellingborough: Patrick Stephens. pp. 9.