The Renault 4P, also called the Renault Bengali Junior, was a series of air-cooled 4-cylinder inverted inline aero engines designed and built in France from 1927, which produced from 95 hp (71 kW) to 150 hp (110 kW).

Charles Lindbergh's Atlantic Ocean crossing in 1927 inspired Renault to enter the light aero-engine market to diversify the range of engines they offered. The resulting Renault 4Ps, with 115 mm (4.5 in) bore and 140 mm (5.5 in) stroke, delivered 95 hp (71 kW) and proved popular, later versions powering several record-breaking light aircraft.

Developed by Charles-Edmond Serre, by 1931 the 6.3-litre 4Pdi had evolved to give 110 hp (82 kW) to 120 hp (89 kW), with the adoption of 120 mm (4.7 in) bore steel cylinder liners, aluminium alloy cylinder heads attached by long studs to the crankcase, Duralumin connecting rods and magnesium alloy crankcase.

The 4Pei was produced in the USSR, with local equipment and features from the MV-6, as the Voronezh MV-4 (Motor Vozdushniy / Motor Voronezhskiy - air-cooled engine / Voronezh built engine {correct interpretation is unclear}).

In 1946 production of the Renault 4P-01 resumed at the SNECMA factory at Arnage, until 1949, with at least 762 engines manufactured.

Renault 4Ps

The initial version with 115 mm (4.53 in) bore and 140 mm (5.51 in) stroke, delivered 71 kW (95 hp)

Renault 4Pa

Renault 4Pb

upright 71 kW (95 hp) / 298 lb (135 kg) - Caudron Luciole

Renault 4Pbi

Inverted development of the Pb retaining the 115 mm (4.53 in) bore

Renault 4Pc

Further development of the Ps retaining the 115 mm (4.53 in) bore

Renault 4Pci

inverted 4Pc

Renault 4Pde

Renault 4Pdi

Inverted, introduced 120 mm (4.72 in) bore steel cylinder liners, aluminium alloy cylinder heads attached by long studs to the crankcase, Duralumin connecting rods and magnesium alloy crankcase. 110 hp / 150 kg - Hanriot 16, 120 hp / 155 kg - Caudron Phalène

Renault 4Pei

Inverted, rated at 110 kW (150 hp) for take-off, the 4Pei entered production before WWII^[1]

Renault 4Pfi

Renault 4Pgi

Inverted lower rated version, giving 78 kW (105 hp) for take-off, using 73-octane fuel.^[1]

Renault 4Po

Renault 4Poi

100 kW (140 hp) with fuel injection.

Renault 4P-01

Postwar production version of the 4Pei, rated at 145 hp (108 kW) for take-off.^[2]

Renault 4P-03

As the 4P-01 but with an inverted flight Zenith carburettor^[2]

Renault 4P-05

As for the 4P-03 but with a modified oil system^[2]

Renault 4P-07

As for the 4P-03 but with a modified carburettor^[2]

MV-4

Licence production of a 110 kW (150 hp) Renault 4Pei variant in the USSR at the Voronezh factory. 180+ were built in 1939 before production ceased, due to a shortage of indigenous carburettors.^[3]

Data from Aircraft engines of the World 1946.^[2]

• Type: 4-cylinder naturally aspirated air-cooled inverted in-line piston aircraft engine
• Bore: 120 mm (4.7 in)
• Stroke: 140 mm (5.5 in)
• Displacement: 6.33 L (386 cu in)
• Length: 1,729 mm (68.1 in)
• Width: 480 mm (19 in)
• Height: 708 mm (27.9 in)
• Dry weight: 147 kg (324 lb)

• Valvetrain: Pushrod-actuated, single intake and single exhaust valve per cylinder
• Fuel system: 1x Zenith 601GS down-draught carburettor
• Fuel type: 80 Octane petrol
• Oil system: Pressure fed, 3.0 kg/cm² (43 lbf/in²), dry sump
• Cooling system: Air

• Power output:
  
• 145 hp (108 kW) at 2,450 rpm at take-off
• 140 hp (100 kW) at 2,400 rpm at sea-level normal
• 110 hp (82 kW) at 2,200 rpm at sea-level cruise
• Specific power: 17.15 kW/L (0.38 hp/in³)
• Compression ratio: 5.8:1
• Specific fuel consumption: 0.186 kg/kW/hr
• Oil consumption: 0.005 kg/kW/hr
• Power-to-weight ratio: 0.74 kW/kg

Comparable engines

• de Havilland Gipsy Major
• Menasco Pirate

Related lists

• List of aircraft engines

• Gérard Hartmann, Les Moteurs d'avion Renault
• Wilkinson, Paul H.. Aircraft Engines of the World 1945 3rd edition. Paul H. Wilkinson. 1945. New York.
• Wilkinson, Paul H.. Aircraft Engines of the World 1946 revised edition. Sir Isaac Pitman & Sons Ltd.. 1946. London.