Renault 70 hp

The Renault 70 hp or Type WB was a French V-8 aero engine that first ran circa 1907. It was also manufactured under license by Renault Limited of West Brompton, London between August 1914 and December 1918, three other companies, including Rolls-Royce, also produced the engine. A variant known as the Type WC used an external oil pump as opposed to the internal pump of the Type WB.[1] The Renault V-8 engines were noted as inefficient but reliable, the inefficiency being mainly due to the excessively rich fuel/air mixture used to assist cooling.[2]

70 hp/Type WB
Type	Air-cooled V-8 piston engine
National origin	United Kingdom
Manufacturer	Renault Ltd Rolls-Royce Limited Wolseley Motors Limited
First run	c.1913
Major applications	Airco DH.1 Royal Aircraft Factory B.E.2 Farman MF.7
Number built	227
Developed into	Renault 80 hp

Applications

• Airco DH.1
• Armstrong Whitworth F.K.2
• Armstrong Whitworth S.S.27 airship
• Blackburn Type E
• Bristol B.R.7
• Central Centaur IVA
• Farman MF.7 Longhorn
• Farman Shorthorn
• Flanders F.4
• HMA no.2 airship, short-lived modification
• Royal Aircraft Factory B.E.2
• Royal Aircraft Factory F.E.2
• Royal Aircraft Factory R.E.1
• White & Thompson Bognor Bloater

Preserved engines

• A partially cut open Renault 70 hp engine is preserved at the Norwegian Museum of Science and Technology (photo)

Specifications (70 hp)

Data from Lumsden [1]

General characteristics

• Type: Inline air–cooled, upright, 90-degree, V-8 piston engine
• Bore: 3.78 in (96 mm)
• Stroke: 4.72 in (120 mm)
• Displacement: 423.76 cu in (7 L)
• Length: 45.5 in (1,156 mm)
• Width: 29.8 in (757 mm)
• Height: 32.8 in (833 mm)
• Dry weight: 396 lb (180 kg)

Components

• Valvetrain: Single overhead exhaust valve, single side inlet valve per cylinder.Although this valve arrangement is cited as "one side and one overhead valve," both valves are situated in a lateral pocket from/to which gases flow. Therefore both valves are "side valves" one on top of this lateral pocket and one on its bottom. There are no valves on the combustion chamber or on the overhead position.
• Fuel system: Single carburettor
• Fuel type: 40–50 octane petrol
• Cooling system: Air-cooled
• Reduction gear: 0.5:1, left hand tractor (There is no reduction gear as such; The reduction is achieved by mounting the propeller on the camshaft.

Performance

• Power output: 70 hp (52 kW) at 1,750 rpm (takeoff power)
• Specific power: 0.17 hp/cu in (7.4 kW/L)
• Compression ratio: 4.12:1
• Power-to-weight ratio: 0.18 hp/lb (0.28 kW/kg)

See also

Related development

• ADC Airdisco
• RAF 1
• Renault 80 hp

Related lists

• List of aircraft engines

References

Notes

1. Lumsden 2003, p. 180
2. Gunston 1989, p. 135.

Bibliography

• Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9
• Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.

External links

• Photo "Flymotor Type 70 hk Renault" (side view), Norsk Luftfartsmuseum
• Photo "Flymotor Type 70 hk Renault" (front view), Norsk Luftfartsmuseum