MOTOR NOTES

Evening Star, Issue 23695, 1 October 1940, Page 2

MOTOR NOTES

fßy ‘ Radiator.’] LIGHTING-UP TIMES To-day .... 7.14 Tuesday ... 7.15 Wednesday 7.10 Thursday 7.18 Friday ... 7.19 Saturday ... 7.20 Sunday ... 7.22 This mouth’s coupons—lo and 11. WATER INJECTION /■ ~ For some 30 years inventors and_ engineers have been toying with the idea that water injection, properly controlled, would improve the running of internal combustion engines. Their belief is that if water were injected in sufficiently limited quantities to avoid appreciable interference with the normal progression of combustion, it would tone down the sharp hammer blow of the explosion into something approaching the action of steam. This idea has so far been found unworkable, and little has been heard of it during the last decade. However, in the opinion of L. Mantel!, a loading English expert on automobile engines, there is now a better chance of this subject being revived and investigated further, owing to the knowledge gleaned during tho last few years of combustion and flame propagation, controlling factors which have baffled earlier engineers. This knowledge, according to Mantell, may yet result in water injection being correctly applied in certain types of lnghoutput engines. The main reason for early failures and recent research successes is that, whilst water is an excellent antidetonant, it is only so at very high temperatures and pressures, which means that it can only be used to advantage in high-compression engines. The higher the combustion heat, the more pronounced tho effect. Tests have shown that the quantity of water injected must be in close conformity with the moan elfcctive pressure. In the past occasional successes were obtained by inventors when certain controlling conditions fortuitously com-, bined, but could not always bo repeated because their nature was not recognised. Recent experiments on the test bench indicate that excellent results can he obtained with modern equipment and suitable engines. Using a oin x single cylinder experimental unit with a very high compression ratio, as compared with the modern automobile engine, the M.E.P. was raised by water injection from 132 to 189, with the carburettor set for maximum economy. With the carburettor sot for maximum power the M.E.P. rose from 191 to 217 when water was injected. The amount of water consumed in these tests was considerable, ranging from 12 to 14 pints an hour, which would, of course, rule out the adoption of water injection where most touring engines are concerned. _ At least for tho present water injection as a power and economy boost can ho dismissed as far as its early application to motor vehicles is concerned, but maybe in the not far distant future more will he hoard of this intriguing subject. LITTLE ENGINES WITH BIG PILLS A Chicago fuel expert has described a new fuel of 125 octane rating, with which he envisages a now era in road vehicles powered by tiny units. At present it costs £lO a gallon to produce this new fuel, but in the fullness of time it will be nearer present-day prices, he prophesies. AMERICAN MODELS At present most of tho U.S.A. car manufacturers have practically closed down on the production of their 1940 models, and are busy concentrating on the needs of their 1941 programmes, but, despite this, the leaders of the industry are keen to apply every facility they possess to the production of the Government’s defence needs. Unfortunately there has been considerable delay in this' connection. This, it is stated, was due to members of the industry being asked to' sign contracts -which were literally a “pig in a poke.” They were asked to sign sealed bids for intricate and costly mechanism, of which they had no experience in building, and asked to take a gambler’s chance on being able to net” even the small profit of 8 per cent, as limited by Congress. It was contended by members of the industry that the best way of getting the vast U.S.A. motor plants under Way on defence equipment was to place original orders on a cost-plus basis. The U.S.A. Defence Commission, which comprises tho best production brains in America, has been hard at work endeavouring to expedite matters, and that success has been attained is evidenced in the cabled reports that some of the big U.S.A. motor plants have already undertaken the production of aviation engines, tanks, and other military equipment on behalf of Great Britain.