FRONT-WHEEL DRIVE.

New Zealand Herald, Volume LXVII, Issue 20668, 13 September 1930, Page 12 (Supplement)

FRONT-WHEEL DRIVE.

ADVANTAGES ON THE ROAD.

DEVELOPMENT FROM RACING,

Just as four-wheel brakes have proved to bo tho outstanding mechanical innovation for tho post-war decade, 1919-1929, so does it appear that front-wheel driving may well constitute the chief feature in chassis development during tho next few years. In each case extensive tests on racing cars formed a prelude to tho use of the new inothod for everyday automobiles, The success of a front-drive chassis at Indianapolis recently, may be taken as proving firstly that this type of transmission can be made to afiord tho necessary durability, and secondly that it provides definite advantages in respect of road holding and cornering. Three things may therefore be accepted as having been proved, these being (1) that front-wheel driving provides certain definite advantages not obtainable with a rear-wheel drive; (2) that there is no insurmountable difficulty in providing a thoroughly reliable and durable front-drive mechanism, and (3) that front-wheel driving has a definite appeal to the public as being a new and interesting .development worthy of special attention. Consequently, there is little doubt that for 1931 the ranges of cars of this type available will bo extended quito materially.

The Bear Springing

The rear wheels may either be mounted on a light cranked axle or may be carried independently upon pivoted levers. The independent principle has much to commend it as it reduces unsprung weight, and furthermore, by allowing the wheels to move up and down without tilting, enables a wider bo'dy to be fitted for a given track. It is no exaggeration to claim that front-wheel driving has an added attraction in virtuo of facilitating the individual and independent springing of each wheel, so rendering axles unnecessary and greatly improving riding comfort. The vertical range of movement of the front wheels need not bo very great; consequently, there is no difficulty in driving them by cardan shafts from a final drive built in unit with the gear-box and carried by the frame. The rear wheel springing, upon which the comfort of the passengers chiefly depends, can be made extremely flexible as there is no drive to impose limitations on their range of travel-

Lightness of Steering.

Contrary to popular belief, tho steering of a front-drive car is not rendered heavier to control by the transmission mechanism. This is probably duo to the fact that when the front wheels aro driven it is not necessary to. employ a castor angle stich as is required to give stability- to tho steering of an ordinary car. The absenco of castor reduces the effort required to move the wheels, and thus amply compensates for tho drag produced by the transmission. A point which should appeal to owner-drivers is that with the engine, gear-box and final drive all in one unit at the front, there is no reason why a single oil filler should not suffice for the whole job. This can bo accessibly placed under the bonnet in tho usual way, and compares favourably with the oil fillers ordinarily located on the orthodox gear-box and rear axle under the floor. The fact that there is no mechanism of any kind under the body of a front-drive car naturally reduces the number of inaccessible points requiring lubrication. Furthermore, the body builder is given a free hand, and can provide a flat, lowlevel floor.

FIRST-GRADE PETROL.

There are undoubtedly many motorists who do not sufficiently realise that the best grades of petrols aro the cheapest in the long run, and imagine that to save a penny or two-pence upon a gallon of fuel is to effect a real economy. The saving of about 2s in the replenishment of the tank can very quickly be wiped out by the possible loss of considerable time in endeavouring to start the engine from cold, and the cost of recharging a completely run-down battery. Nor are these all the items that fihould be taken into consideration. For example, in a cold engine inferior spirit will not vaporise quickly, and with tho constant working of tho self-starter a considerable amount of petrol is drawn into the cylinders of tho engine, washing the lubricant off tho pistons and walls, thus encouraging wear and tear; and also descending into the sump it tends to destroy the lubricating qualities of tho oil. So serious is this effect that some engines are equipped with an oil refining ivpparattis, tho main purpose of which is to eliminate this kind of adulteration. It is thus evident that it is always worth while to use a fuel which has quick starting properties, which means that it contains fractions which will readily evaporate. In the interest of saving in wear and tear, to say nothing of time, the engino cannot start too quickly.

TESTING COMPRESSION.

The use of the self-starter has reduced tho ease of making compression tests. When tho crank was used to start tho Engine more opportunities were given to test tho compression. Whenever thero is any sign of loss of power tho starting crank should be used to see if the compression is good. Do it now while the engino is in proper condition, and then thero will bo a basis for comparison.