LightAuto

An insight into the British motoring scene ninety years ago.

 Extracts from the Sixth Edition of the Autocar Handbook.

Estimated date of publication 1914.

The Light Car.

The feature of the automobile movement which has attracted most interest during the past few years, has been the development from the embryo to a very highly finished article of the small car designed to meet the requirements of those who, aspiring somewhat higher than the motorcycle and sidecar, are unable to afford either the purchase price or the running costs of what may be described as the full sized car.
To a very great extent we have to thank experience gained at Brooklands (Britain's only motor racing circuit at the time) for the advent and rapid rise to fame of the light car, for without the knowledge obtained on the track in the direction of securing the uttermost iota of efficiency from an engine of a given cylinder capacity, we should never have achieved the success which is ours to-day in light car design and construction.
A few years ago the man would have been looked upon askance who advocated the use for ordinary touring work of a chassis equipped with an engine of which the cubic capacity of the cylinders did not exceed 1,100 c.c. ; Yet so vast have been the strides made within the past few years that, not only have some altogether remarkable speed records been established by small cars with engines below the 1,100 c.c. mark, but many firms are to-day producing thoroughly sturdy little touring cars with motors of this size.
We mention the 1,100 c.c.  mark for the simple reason that it has been adopted by the Royal Automobile Club and the Auto Cycle Union as the Maximum engine size foe a vehicle which is officially known--for competition purposes--as a cycle car. The great majority of machines so styled have in reality no resemblance whatever to motor cycles, and it should be realised that the name "cycle car" is to be taken rather as a means of indicating the engine size of a light car than as denoting a special type of vehicle in which motor cycle characteristics predominate.
As a matter of fact, no definition of a light car exists beyond the fact that the R.A.C. has so far limited the size of engines for light cars in trials (A form of motor sport popular at the time, that included an element of off the road driving) to 1,400c.c. ; Nor indeed would it be very easy to devise a definition, since there is between the light car and the large car no great gulf fixed, but merely a line of demarcation.
While in design the "orthodox" light car is, to a great extent, a copy in miniature of the large car, there is in the case of low-powered chassis generally rather more divergence in the views taken by designers than the case with larger vehicles. This not altogether to be wondered at, for the light car movement is yet young, and it has not yet assumed that aspect which is a feature of the world of large motor vehicles. In this respect the light car and the large car are distinct, for in the case of the latter the design has become standardised, and save for comparatively minor points, there is not much to distinguish one from another. While it would not be accurate to say that the light car has reached a standard design, there can be no doubt but that it is gradually settling down to an orthodox pattern which follows the details of the larger cars, yet there are other types which keep it from being referred to as standardised.
In the first place, there is the light car designed and built throughout on what may be described as orthodox large car lines-- that is to say, the light car with a four cylinder engine, thermosyphon water cooling, high tension magneto ignition, lubrication by pump and troughs in the base chamber, a leather cone or disc clutch, a gate-operated gear box giving three forward speeds and a reverse, propeller-shaft transmission to a bevel or worm-drive live back axle, worm and segment steering, and pressed steel frame. The determining factor between this class of vehicle and somewhat less orthodox, but perfectly successful light car chassis, is not that of engine size, for such small cars as we have outlined are to be found with engines ranging from below 900 c.c. to whatever maximum limit it may be decided to adopt.
The we have the light car, of which the engine has a single or twin cylinders, with water cooling and other features which have come to be regarded as standard car practice, but of which the transmission system is of a type found on larger cars. Among light car designers there are a few who incorporate chain drive to convey the power from sliding pinion gear boxes to the rear axle, but this form of transmission is not in very general use. There are one or two examples of light cars in which friction drive is employed, the drive disc rotating on an extension of the crank shaft, while the driven disc, which is as a rule, surfaced on its periphery with compress paper, is designed to slide upon a transverse shaft, the final drive from the lasted named shaft to the road wheels being by chain.
Another form of friction-driven light car is that of which the G.W.K. is typical, in which the position of the engine enables the final drive to be by propeller-shaft to an orthodox live axle. It is only fair to mention that it is largely due to the efforts and successes of the manufacturers of the G.W.K. that friction drive for small cars is now admitted to be a perfectly practical proposition.
The reference which has been made to the G.W.K. brings us to the consideration of another point in which divergence from large car practice is sometimes found. Especially where the manufacturer has set low first cost as one of the most important ends to be achieved, we find that a V twin-cylinder engine is sometimes adopted. A few designers of two-cylinder engines rely upon air-cooling, but the majority incline to the adoption of water-cooling, even though it entails a little extra complication and some additional weight. Really admirable examples of the two-cylinder light car are in existence today, and he would be a bold prophet who would say that this type of motor is doomed to disappear at an early date.
Finally we come to a class of light car which clearly shows that it has been evolved from the motor cycle. Here we find that the final drive to the rear wheels is by means of two belts. Belt drive was frequently adopted on the earlier cycle cars; but for one reason or another it fell into disrepute, and, although there are still one or two satisfactory belt-driven four-wheelers, the vast majority of small cars are equipped with transmission by geared propeller-shaft.
In addition to light cars proper, there are still made a few passenger-carrying three-wheeled machines, which have survived the test of time and have proved themselves quite capable of competing with small four-wheeled cars. The two three-wheelers which are most in evidence at the present are the Morgan and the A.C. ; of these the former has achieved some remarkable performances on the Brooklands track, and is a very speedy little vehicle for touring purposes. Whether or not the three-wheeler will continue to appeal in time to come, when the price of the four-wheeled light car has been further reduced, remains to be seen; its lightness and low running cost are in its favour, but, on the other hand, in comfort, and especially in the space available for luggage carrying, it cannot compare with the four-wheeler.
Motoring For the Masses Part two
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