Forethought.

Forethought. ” “

” Forethought saves Afterthought ” is the purpose behind a booklet published by the Dunlop Rubber Company, Ltd.. which every motorist, however experienced he may be, would do well to study. As is pointed out in the Introduction, tyres really need very little attention, but that little is essential.

After surveying the principle and purposes of the modern tyre, the important subject of inflation pressures is fully discussed. This section contains a vast amount of useful information, and no motorist with the knowledge given here will allow his tyres to wear excessively through ignorance. Realising the results of certain treatment, he will automatically take the necessary precautions to relieve his tyres of unnecessary strain.

Other subjects dealt with fully are valves, pressure gauges, storage, repair of cuts and other damage, alignment of wheels, and an interesting chapter on ” Why Tyre Results Vary.” Those who find difficulty in the attaching and removal of tyres will find the solution of their difficulties in this booklet, and there is a table of data with regard to interchangeability.

” Forethought ” is profusely illustrated, and a careful study of its interesting pages is bound to result in reduced tyre wear and lower running costs. MOTOR SPORT readers can obtain copies, post free, from the Advertising Dept., Dunlop Rubber Co., Ltd., St. James’s House, St. James’s Street, London, S.W. 1.

A Well-made Performance Meter

If a sports car is to be kept in perfect tune some guide as to its performance is essential. None better can be found than a reliable gradient and performance meter, and one of the finest instruments of this type we have ever inspected is the Ott-way. The manufacture of instruments and gauges is a highly skilled craft, requiring years of experience, and the firm of Messrs. W. Ottway & Co., Ltd., Orion Works, Ealing, has specialised in this work since the year 1604. Such delicate devices as naval gun sights,

telescopes, surveying and mining instruments, micrometers, etc., demand a degree of accuracy which places their latest product, the Ottway Gradient and Performance Meter, on a very high standard indeed.

As its name implies, the instrument enables the driver to ascertain the gradient of hills and to know whether he is obtaining from his car the performance which should be expected, both as regards the pulling power of the engine and the efficiency of the brakes. The Ottway meter depends for its operation upon the deflection of a pendulum, which is suspended in an oil-filled container for damping out any violent oscillations due to road shocks. The pendulum is geared to the pointers, of which there are three, one after another, so a.s to give a good open scale for accarate readings.

In addition to measuring the gradient of hills, which should be done with the car stationary or running at a constant speed, the Ottway Meter will provide an accurate indication of the acceleration and braking efficiency of the car, the gradient which the car can surmount on each gear (particularly useful when a caravan-holiday is being planned). and the power of the hand brake to hold the car on a gradient.

Altogether a most instructive accessory for the keen sports-car owner, accurately constructed and beautifully finished.

“Blue Bird’s” Records.

The four world’s records annexed by Sir Malcolm Campbell with “Blue Bird ‘ have now received the official confirmation of the A.I.A.C.R. The car is designated the Campbell Special, and the speeds attained were as follow :

1 kilometer ‘(f.s.), 276.16 m.p.h. (Campbell, 272.46 m.p.h.).

1 Mile (Ls.), 276.82 m.p.h. (Campbell, 272.11 m.p.h.).

5 kilometres (f.s.), 268.47 m.p.h. (Campbell, 257.30 m.p.h.).

5 miles (f.s.), 251.40 m.p.h. (Campbell, 242.75 m.p.h.).

It is interesting to observe that on this occasion the mile record is faster than the kilometre, whereas in 1933 the position was reversed.

DRIVER, KNOW YOUR PLUGS!

HOW many drivers of touring cars could tell without looking under the bonnet the type of sparking plug fitted to their engines ? Probably not more than one in ten, for the engine in this class of vehicle probably remains undisturbed until renewed at the annual ” decoke ” and overhaul. The sports car owner takes a much closer interest in the workings of his mount, while to the racing driver who warms up on ” soft ” plugs, probably tries a few practise laps, and finds signs of fouling or overheating, such a knowledge is essential.

It is not difficult to memorise a few of the type numbers, but the range of plugs is continually being expanded, especially in the high-duty range, and the latest Champion Type Selector shows some thirteen of the 18 mm. size and seven of 14 mm. pattern plugs suitable for fast cars. This variety of types is a little confusing even to the enthusiast, since the numbering is more or less arbitrary, but with the aid of an ingenious but simple indicator integral with the chart, the wisest type can be selected without difficulty.

The lists are printed in parallel columns, and a perforated slider is moved so that one of its slots reveals the type of plug in use. If a cooler-running type is required the two next highest in this direction are shown in a second window, while to combat oiling-up or sooting, use would be made of one of the two hotter-running types shown in the window below. The back of the Type Selector gives a list of sports and touring cars and the type of plug recommended.

The chart is printed on stiff glazed card nine inches by three, and may be obtained from the Champion Sparking Plug Company, 83, Pall Mall, London, S.W. 1, on mentioning “Motor Sport.”