MOTORING WORLD

Manawatu Standard, Volume XLVI, Issue 23, 26 December 1925, Page 3

MOTORING WORLD

MOTORING AND CYCLING NOTES. SMALL LIGHT CAR, American automobile interests are still endeavouring to secure holdings in leading English motor concerns. It will bo remembered that General Motors (U.S.A.) negotiated for the controlling interest in the Austin Manufacturing Co., England, but the shareholders" were not agreeable to the proposition. It is now reported that the same big American Corporation is negotiating with the Vauxliall Co., another prominent English car manufacturer, with a view to securing an interest in that concern. It is apparent that at last the American automobile manufacturer is awake to the fact that the development and growing popularity of the high efficient British and European light small car is beginning to affect the export automobile business of America. That the matter is seriously regarded in U.S.A. is evident from a recent warning issued by the Government Department. of Commerce at "Washington informing the United States motor manufacturers that they must immediately cope with the problem of the rapidly growing popularity of the British and European type of small highly efficient engined car if they <lesired to maintain their export trade. The result is that a campaign is to be organised with a view of building the American export trade in automobiles up to 2,000,000 cars per annum. Considering that America only exported 278,730 cars last year, it will be realised the efforts U.S.A. is going to make to hold and increase its overseas trade. ENGINE CAPACITY. In pre-war days a car engine with a capacity of less than 3 litres was considered, says The Motor (England), to bo under-powered for really serious touring work, and practically all the more popular cars at that time exceeded this capacity. Nowadays, however, a 3-litre engine is considered quite large, and most of the well-known English and Continental makes provide a road performance equal to, if not better than, the prewar car of perhaps twice the capacity. Economy, too, has been effected, r.t any rate, in respect to the amount of petrol and oil used and the number and size of tyres necessary for a given distance. In a total mileage of, say, 30,000 or 40,000, these economies total a considerable amount. Has the limit been reached where the engine capacity cannot bei reduced still further without affecting materially the performance of the car on the road? To turn for a moment to Brooklands racing track (England), it is certainly a very strange sight to see one ot the old-time giants, with an engine of perhaps 10,£J0 c.c. or 12,000 c.m capacity, being handsomely beaten by a tiny projectile with it miniature engine within the light car limit (i.e., 1500 c.c.) —and at a most astounding speed, too. As would be expected, the large car is also very heavy, and, by virtue of its size, although the available hose-power of the larger ■engine may be slightly greater than that of the smaller one by which it is beaten, these factors of weight and size are of great moment when performance on the road is being considered. At the present moment there are several 1500 c.c. racing engines with a maximum power output of over 100 b.h.p., but in the touring type of engine (almost without exception) a capacity of three litres, or even four litres, is required in order to get an equal performance. Now these 4litre engines are installed ill largo chassis, and a great number of them are equipped with fairly light bodies. Their performance, however (with a touring type of body), is probably in the neighbourhood of 60-70 ni.11.p., whereas the 1500 racing car is capable of speeds considerably in excess of 100 m.p.h. Is it not probable that the car of tlic future will closely follow the lines of the present day racing car?

A comparison of tho two types might prove illuminating, especially if the weights and available horsepowers are included. A representative 3-4 litrei chassis will weigh at least 28 cwt., while a 1500 e.c. racer weighs about 11 cwt.—considerably less than half the weight of the larger type. The weights of the engines would probably be in the same proportion. Now, an engine of 1500 c.c., in order to develop 100 li.p., would doubtless bo fitted with a supercharger, and this horse-power would be available at a “peak” speed in the region of 6000 r.p.m., as against the largo type of engine whose maximum power is developed at about 3000 r.p.m. Tno revolution speeds, therefore!, of the two engines are in the neighbourhood of 2 to 1, and, as tho stresses in the transmission decrease in revolution speed, it is clear that the highspeed type of engine can be equipped with considerably lighter parts tnan tho low-speed type, tor equal strength. Again, a great reduction in weight is possible in all components such as the engine, gear box, clutch, front and rear axles, etc. This done the chassis frame itself can ho made lighter with a consequent reduction in tlie size of tyres and wheels required. Thus the complete car can he made with equal body space to that available on the larger chassis but at a traction of its weight.

The foregoing has been confined chiefly to tne advantages to be gained from a reduction in weight oi the car as a whole, and a briel review of some of these advantages would perhaps be interesting. JLet us assume that fivo people, averaging 10 stone each in weight, are being transported on an average fairly hilly country in the two types of car mentioned above with bodies of equal weights—say, cwt. In the case of the racing car tho total weight would be 11 cwt. (chassis) plus 3J cwt. (.body) plus Oj cwt. (passengers), making a total of 20J cwt. In the case of thei normal touring car there would be 28 cwt. (chassis) plus 3£ cwt. (body) plus 6 (passengers) making a total of 372 cwt. Now, assume a road speed of 30 m.p.h. up a gradient of, say, 1 in 8, the horse-power required for the two cars under review purely on a weight basis and excluding windage (which would probably he roughly proportional to their weights at such a comparatively low speed as also would be the frictional resistance in tho mechanism of the chassis) would compare as 42 b.h.p. to 23 b.h.hp. approximately, which is nearly in the order of 2 to 1. Again, in acceleration the horsepower required for a predetermined increase in speed would be proportionately lower as the weight of the vehicle decreases.

On the level the cars would, theoretically, require equal propulsive efforts, but this does not work out in practice, as the frictional resistance in tho mechanism of tho chassis tho tractive resistance of the tyres and the wind resistance of tho car as a whole would vary, roughly, in proportion to their respective weights.

If it be admitted that an engino of just over one litre capacity should pro-

vide the desired road performance when installed in a suitably light chassis, why, then, is this not done? In the first place, tlvo very small supercharged • racing engine is still in its infancy, but it is being steadily developed in all the big races now being held, and, in the opinion of the writer, it will not be long before a chassis will he seen on the road with, say, a 10ft wheelbase, amjile accommodation for five people, and a miniature supercharged engine of 1000 c.c., or 1100 c.c- capacity, developing- its power at 6000 r.p.m. . . All the modern tendencies in design are toward a general reduction in weight, particularly of the reciprocating parts of the engine, which in itself allows a higher revolution speed to be attaned with safety. As further developments occur, methods will doubtlessly be found to run an engine at those iiigli speeds with silence and sweetness, and such a type promises to be the car of the near future. NEW SPEED TRACK AT MAItOUBA. The new auto speed track at Marouba, near Sydney, was opened recently, and drew a huge crowd of some 70,000 spectators. Some thrilling racing was witnessed, the fastest pace being attained by the motor cyclists, who touched over 90 miles pA>. hour, in fact, tli& New Zealand crack. Spencer Stratton, reached 95 m.p.li., the fastest speed yet recorded on a track in this part of the world. The final of the five miles scratch race for cars of 3000 c.c. and under provided a thrilling contest. -The two fastest cars on the track were driven by R- _ Garlick and A. V. Turner. The drivers, evidently from want of experience, could not hold the turns after coming off the steep bunking, but no doubt as the drivers become better acquainted with the track some tall speeds will be attained. VARIOUS NOTES, The effect of the sustained high price of crude rubber is that American tyre manufacturers have made five increases in motor tyre prices since May last. In Australia there have been two increases from the same cause. Motorists in this country _ would be well advised to procure their tyre replacements whilst the present prices hold, for with rubber in the region ot 4s 6d per pound current figures may not last. Many motorists are now making arrangements for their holiday tour, and the holiday season is seeing few fumily cars idle. It is a time when motorists are to bo envied. Erco of trams and trains, etc., they can travel when and where they like.. It is a time, too, when motorists above all things desire the absence of roadside tyre trouble. The best plan is to temporarily discard the nearly worn out covers and fit new, dependable tyres and thus ensure freedom from tyre troubles during the holiday season. The old tyres cun bo fitted again later and worn right out under conditions where tyro troubles are not such a bugbear. It is remarkable what the presentday car is capable of when put to the test. In a reliability demonstration made with a 12 li.p: ear ill France recently, 18,630 miles were covered oil the road before it eame to a stop: Three sets of drivers were used, and the test lasted 30 days: The test was controlled by the Automobile Club of France. In reality the cat did two years’ running iii one month; Particulars are to hand of one of the finest sustained speed efforts yet recorded by. an automobile* The achievement was one by, Messrs Garfield and Plessier on. a six-cylinder 45 h.p. car, upon which they covered iUdO miles in Olirs 49mins 45secs, and 1204 miles in twolve hours. To average 100 1-3 miles an hour for twelve hours, including stops for change of drivers, fuel, etc, is indeed a wonderful performance. The record was put up on the Montlhery track, near Paris. There appears to be some doubt m respect to the remarkable speeds attained by Paul Anderson, the American crack, on the occasion of the records meeting held at Arpajon, near Paris, on October 11, brief particulars of which were cabled at the time. The official figures issued by tlio Motor Cycle Club of Franco show that Anderson covered the flying mile (both ways) at an average speed of 218.421 k.p.h., which represents approximately 136 m.p.li. It is estimated that over tlio flying mile (one way) his time was 22.635ec5, which works out at the terrific speed of over 160 m.p.h. Unfortunately, however, there appears to be some doubt as to the correct working of the electrical timing apparatus and, although Anderson did make some remarkably fast times, it is probable that the figures given are open to discussion. It is certainly rather curious that his speed over the flying kilometre was only 194.594 k.p.h,, which represents a speed of about 121 m.p.h., whereas his speed over the flying mile shows 15 miles more.