MOTOR AND CYCLE.

Taranaki Daily News, 25 February 1919, Page 6

MOTOR AND CYCLE.

] NEWS AND NOTES. Economy is now a very important consideration in connection with the use of motor cars, and will remain so for a considerable period, even now that the war has ceased. There are various directions in which economics can be effected, so as to compensate, to some extent, for abnormal cost of petrol and oil. The carburettor is the liret point to deal with. In most cases of cars which have been_used for a considerable period it will bo found that the carburettor is exceedingly wasteful, and that the petrol consumption has steadily risen. The remedy is to tune up the sarburettor specially, with the object of getting the best fuel results, and keep it up to concert pitch. Many motorists are quite capable of undertaking this work; others are not, and in the hitter case they should go to an expert who is used to dealing with carburettors- We have known as Big a difference as five or six miles to the gallon being accomplished with a minimum of trouble by an expert who understood his work. An extra air valve is another method of effecting economy, but its successful operation depends on the driver. If the latter does not take the trouble of learning by experience the positions which approximately give the best results under varying circumstances lie had better be without the appliance. In buying a new car, the man who finds it necessary to economise should make sure that it is litted with a carburetter which has a reputation for economy. Both engine speed and car speed {ire also important factors as regards the consumption of petrol. The air resistance increases as the square of the velo. city, and, consequently, at high speeds it takes a great deal of power to overcome this resistance. On the other hand, the interna! combustion engine works at its greatest efficiency at its normal speed. It will consequently he seen that from an economy point of view it i- had practice to drive either very fast or very slow. The motorist should. 1 therefore, drive at a car speed which entails running this engine at or about iis normal speed, so far, of course, as h consistent with his convenience and witii the safety of the public. Me should also bear iu mind that to continue too long on the high speed is very wasteful of spirit as the engine is then laboring with fully open throttle, while the car is travelling at a slow pace. It is better to change down and run the engine at its normal speed. This will mate u big difference in petrol consumption olid in many cases the car wil! actually travel faster than it did when the engine was laboring on the higher speed. In ''the trade" there is a distinct tendency, says an English expert, to consider that ihe air-cooled car is ncarrealisation than it lias ever been. No doubt the experience of many car firms who have been connected directly and indirectly with the production of aeroengines will have solved many of the