From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Article from 'The Motor' magazine advocating for oil-engined Grand Prix racing to drive innovation in high-efficiency engines.
| Identifier | ExFiles\Box 128\3\ scan0018 | |
| Date | 14th February 1939 | |
| The Motor 62 February 14, 1939. International Benefit to be Derived from High-efficiency Oil Engines THOSE of us who have known M.{Mr Moon / Mr Moore} A.{Mr Adams} McEvoy for a number of years realize that his suggestion (which appeared in The Motor dated December 20, 1938) for confining Grand Prix racing to compression-ignition-engined cars is based upon a desire to foster engineering progress; it is not merely a stunt. At present the oil engine is a "bread-and-butter" unit in industry, whilst its high-speed versions propel over 5,000 units of railway rolling stock. In Great Britain more than 25,000 such engines are at work in buses and lorries; in Germany the figure exceeds 63,000. In such utilitarian spheres the output per litre is about 15 b.h.p. or a little more. An example of a modern high-efficiency oil engine for aircraft. The Junkers opposed-piston 1,800 r.p.m. unit developing 750 b.h.p. and weighing 1.9 lb. per b.h.p. Oil-engined Grand Prix Racing Cars The German Junkers opposed-piston aircraft oil engines represent the present peak at about 45 b.h.p. per litre. If such a Grand Prix formula were laid down as Mr. McEvoy suggests the immediate technical benefits would be reaped by aircraft engine makers, commercial motor manufacturers and private car makers in that order, with the emphasis very much on the aircraft aspect of the matter. The oil engine is a vital necessity for the betterment of civil aviation, therefore the formula must not confine engine sizes to mere models of what would be required; say 12 litres in the first place as the maximum. At present Capt. G.{Mr Griffiths - Chief Accountant / Mr Gnapp} E.{Mr Elliott - Chief Engineer} T. Eyston holds the C.I. record at 159.1 m.p.h. over the flying kilometre with a 17-litre 12-cylinder-engined car. Weight also would have to be permitted on more generous scales during the first Formula period. A few years ago it was considered desirable to make an oil engine massive to withstand high maximum pressures. Now it is found that pressures need not exceed some 850 lb. per sq. in., and that the rate of pressure rise within the cylinder is less severe than with many petrol engines, so that commercial-vehicle engines of 20 b.h.p. per litre are in production, weighing around 7 lb. per b.h.p. with certain heavy accessories. Airship oil engines of 1,500 r.p.m. D20 maximum speed weigh little if anything more than 2 lb. per b.h.p. At the moment road vehicle oil engines run up to about 4,000 r.p.m., in a few cases and much higher speeds could not be expected at first, therefore freak lightweight engines are not likely to materialize. I see no harm in a 35-cwt. maximum car weight limit, whilst chassis dimensions such as adopted for the six-litre German G.P. cars would need but little increase to permit housing a 12-litre oil engine with much smaller fuel tanks; an oil engine runs nearly twice as far on a given volume of fuel as does a petrol-engined car. G.P. Stimulus Needed British aircraft engine makers are all fully occupied on "death and disaster" products; the Air Ministry would have to encourage them financially and by example to pursue this peaceful avenue of research. The Air Ministry itself has a wealth of pigeon-holed knowledge (dating from Farnborough experiments in 1923) about high-speed oil engines, and Mr. Ricardo is very busy on the problem now. The pressure-charged two-stroke oil engine built in this country and developing some 60 b.h.p. per litre would soon be forthcoming, given the stimulus of G.P. racing. To-day the high-output C.I. engine stands where the racing petrol engine did in 1914. German aeroplanes of the early Great War days had engines developed from those which Mercedes used to win the French Grand Prix of that year. History might repeat itself in that oil-engined aircraft would owe a debt to the racing car, but in a peaceful sphere. The wider use of oil engines in transport work on land, sea and in the air would cheapen power production, conserve the world's oil supplies, minimize fire risks, and bring into the automotive world much new blood, therefore its objects to be attained are worthy of serious effort. As to the response by various nations, Great Britain has attained a standard of commercial oil engine design which is supreme; Germany has 40 years' experience and is as keen as mustard, while America is rapidly becoming Diesel minded and has already come car-racing knowledge with oil engines. The French Air Ministry encourages the aircraft C.I. unit, and so does Italian officialdom. An oil-engined Grand Prix racing Formula should evoke a truly international effort, with national backings because the results would be of national advantage. Who will give the vital lead that will force all hands? D.{John DeLooze - Company Secretary} S. D.{John DeLooze - Company Secretary} WILLIAMS, A.M.I.A.E, Assistant Editor, The Oil Engine. | ||