HAS RACING CEASED TO BENEFIT THE UTILITY MOTORIST? IS THE RACING-CAR OF TO-DAY STILL THE TOURING CAR OF TO-MORROW?
Sooner or later any one who is interested in the sporting side of motoring asks himself to what extent racing has been of benefit to the evolution of the utility car. How much does the normal car user really owe to racing ? In the first post-war motor-racing classic, ” The Lure of Speed,” the late Major Sir Henry Segrave devoted a chapter to answering this question. Segrave pointed out the efficiency Of touring engines of 8 to 12 h.p., the general adoption of aluminium pistons for ordinary power-units, the reliability and quietness of overhead valve operation, the perfection of fourwheel braking, the universal use of detachable wheels, the long life Of valves and valve seats and the lowering of the centre of gravity of touring chassis as valuable factors owing their origin or rapid development directly to racing. If any further proof is needed of the benefits conferred on the every-day caruser as a result of racing we have only to consider the truly remarkable and extremely valuable progress made in
tyre construction. The accident at Fame in 1924, when a tyre, thrown from Malcolm Campbell’s 350 h.p. Sunbeam when that car was travelling at over 140 m.p.h., struck and killed a boy spectator, was largely responsible for the Dunlop Rubber Tyre Co. Ltd. commencing a serious investigation into the whole tyre problem. To-day punctures and bursts are an extremely rare occurrence, even in racing, and you and I are able to tour 20,000 miles Or more On a single set of covers. Racing has also been responsible for many other valuable lessons, from direct knowledge relating to individual power-units and chassis, to more abstract applications concerning metallurgy, detail technicalities, streamline formation, lightweight construction, and so on. Furthermore, every time a car is prepared for competition it is reasonable to suppose that more than one workman is encouraged to give of his best, and even if no fresh knowledge is acquired, the result cannot fail to be of value. Clearly, racing has, in the past, contributed very materially to the evolution and perfection of the ordinary chassis. Indeed, it is difficult to know what sort of motoring we should be enjoying to-day had there been no racing contests to stimulate and teach the world’s designers and technicians,
But has racing continued to contribute these vital lessons during the. past few seasons ? Or is the value of racing declining ? I have quoted from ” The Lure of Speed ” in defence of racing. However, going more deeply into the matter reveals that Segrave mentioned other factors in his book, which he regarded as about to be widely enjoyed byOrdinary drivers thanks to the lessons Of racing-car construction. These features of design were : the straight-eight engine ; large diameter o.h. valves and Central sparking plug in a hemispherical combustion chamber ; and supercharging. Segrave emphasised that the first two features were already corning into the utility car field, and that, while supercharging, except in one conspicuous instance, was restricted to racing vehicles, ” it is quite certain that this will not always be the case.” That was nearly nine years ago. To-day there is certainly some revival Of interest in multicylinder power-units, but ” V ” construction seems likely to be of greater use in the immediate future than the in-line layout, and in general the four-cylinder engine has of recent years more than held its own against the “six.” For racing the eight, twelve, and sixteen cylinder engine provides designers with a means of keeping combustion chambers compact and reciprocating parts light. Problems of balance, distribution and space are easily combated. For utility purposes these problems cannot be banished so easily and they militate against the widespread adoption of multi-cylinder inline engines for their qualities of even torque and rapid acceleration. The single or twin o.h. camshaft operation of valves in hemispherical combustion chambers to-day figures in not more than six British-built production engines. On the Continent the arrange ment is scarcely more popular. Yet camnoise is no longer the objection, as the latest Bugatti testifies. Maximum power output for a given cubic capacity is not the sole requirement of a touring engine, in which .first cost and ease of mainten ance are of considerable importance. For racing purposes it is desirable to use the highest possible compression ratio, assisted by ‘ dope ” fuels, to burn the charge as efficiently as possible, to con duct away surplus. heat from internal parts and to reduce valve-gear inertia to a minimum. Consequently, the true form of hemispherical combustion chamber and twin o.h. camshaft valve actuation, that were featured in the Bugatti, Sunbeam, Fiat and Darracq racing-cars of Segrave’s day, still figures in the specifications of the Alfa-Romeo, Bugatti, Mercaks-Benz, and Maserati Grand Prix cars of 1936. So far as supercharging is concerned, eminent engineers had predicted the wide spread adoption of this essentially raciii development to touring engines long before Segrave wrote his book, and at
frequent intervals since they have continued to stress the various ways in which every-day motoring must benefit from the correct application of forced induction. The fact remains that on the British market lo-day there are only nine makes of car offered in supercharged form. This number includes three cars with essentially American-pattern low-pressure boosters and the Mercedes-Benz, which Segrave referred to in 1928 as the one conspicuous instance of supercharging applied to the standard car ; which marque originally had appeared in this form before using the supercharger for its racing Models. Certainly quite a number of existing engines have been fitted with proprietary superchargers to individual requirements, but this has resulted from interest stimulated by racing designs, and not from knowledge handed on from racing, .which was expected to hasten the adoption of engines built for forced-induction conditions and bringing out all its advantages to the ordinary driver. The important aspect is that of the relation between features developed by racing and the extent to which the motoring public benefits from such features. Clearly, items such as four-wheel brakes, reliable tyres and tubes, aluminium pistons, detachable wheels, overhead valves and
• low chassis frames have come into general use and contribute to the motoring pleasure of a very large number of car users. Whereas the eight-in-line engine, the hemispherical head and the supercharger are features of design employed by only a few designers and, moreover, they figure chiefly on cars which sell in relatively small quantities. Those items of specification that have passed into general use may be said to owe their rapid development to pre-war and early post-Ns ar racing. On the other hand, those items which are still regarded as veryadvanced practice came into being as a result of building racing-cars for contests held under the limited cylinder capacity ruling, which finally specified an engine size not exceeding li-litres. This condition put a premium on extremely high crankshaft speeds and a high degree of volumetric efficiency and developed features that found no place in the sphere of utility car design. Apart from the items already discussed,
oil radiators, ball and roller bearings, separate cylinders, ultra light con-rods and other features introduced during the period have shown no sign of being handed on to the every-day motorist.
To be continued in the February issite.