The trend in racing car design

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In dealing with the trend of design among racing car builders it should first be established where design finishes and where improvisation begins. Naturally, no hard and fast line can be drawn but there are certain racing cars which are designed and built by one man or one factory starting from scratch, and others which are nothing more than an assemblage of proprietary components. In the first case design trends can be followed and assessed while in the second much of what appears to be design, is in reality the use of available parts from production cars modified to suit racing purposes. Under this latter classification come a number of quite successful cars of the “one-off ” home-made type, but these cannot be brought into a discussion on design. In much the same way the question of obsolete cars arises, for while an article on design trends should automatically contain a review of present-day race entries, many of the cars in use today, especially in National events, are outdated and their design has been superseded, so that while the car may still be successful, it cannot be considered to have any bearing of present trends of design. For these reasons this article will deal mainly with the new, or comparatively new, cars in present-day International Grand Prix racing.

As road racing is now nicely defined by three categories it would be simplicity itself to consider each group on its own and follow the trends of thought of the designers of cars in each of the three Formulae. Unfortunately this cannot be done, as design in Formula I is now practically non-existent, such races as there are for this category being supported by long-established cars, there being no incentive for the development of new designs. Similarly, Formula III is a difficult group as so much of the construction of 500-c.c. cars is controlled by the availability of bits and pieces that can be adapted. Pure design, starting with a clean sheet of paper, being very limited in this class, due to its close allegiance with motor-cycle racing where all the serious design of engine and gearbox is carried out, Formula III builders doing the chassis parts only. However, there is sufficient activity in this category to deal with it separately, whereas Formula I can be coupled with the heart of present-day design work—Formula II. In both these categories there are many cars which are still raced though they were designed some years ago, such as the Lago-Talbot, 4CLT Maserati, 2-litre V12 Ferrari, early H.W.M.s and Simca-Gordinis. Cars of this type cannot be brought into the discussion, although modifications of them, such as the Maserati-Platé, can. In the Formula I and II categories it is interesting to list those cars which are designed as a whole in their respective factories and in their respective countries. From Italy come Ferrari, Maserati A6G, and Osca, France offer Gordini, Germany the V8 A.F.M. and o.h.c. Veritas, while Great Britain fields Alta and B.R.M. All these names design and build the complete car, and added to these are many makes that design their own chassis, but use proprietary engines. Cisitalia, Maserati-Platé, Jicey, H.W.M., Cooper-Bristol, E.R.A., Connaught, Aston-Butterworth and Frazer Nash come under this heading, and it will be noticed that Great Britain has more cars in this group than any other country. If we are to learn anything constructive about design trends then we must look to the first list of makes, for it is from these that design, virtually unhampered by the finance bogy, is allowed to flow freely, especially as regards engines and gearboxes.

Dealing first with the main driving force behind any racing car, the engine, we see that the six-cylinder unit is by far the most popular, being made by Gordini, Maserati, Osca and Veritas, whereas only Ferrari and Alta adhere to four cylinders, although Butterworth side-tracks a bit with his unique ” flat four.”  A.F.M. are alone in using eight cylinders, the Küchen design remaining unchanged from its inception two years ago, and B.R.M. are in a similar position in using 16 cylinders. For Formula I Ferrari and Osca retain 12 cylinders, but they are survivors of a dying Formula and one cannot guarantee that Lampredi would retain 12 cylinders for the 4-1/2-1itre Ferrari, were the Formula to be extended for another period. Thus we have but five newly designed engines for present-day racing, Gordini, Maserati, Osca, Alta and Ferrari and as the Alta is known to have a new design to replace it, we can safely say that the trend in engine layout is towards six cylinders, especially for the existing Formula II, and in all probability for the 1954 Formula for 2-1/2-litre engines. Added to this is the weight lent by Frazer Nash with their B.M.W.-based six-cylinder and the o.h.c. Veritas six-cylinder designed by Ernst Loof, though neither of these are current designs, but are developments of an earlier period. Obviously one cannot include users of Bristol engines, such as Cooper and E.R.A., or Alta engines, like the H.W.M., the Platé cars with modified out-of-date four-cylinder Maserati engines, the Cisitalia with its B.P.M. marine engine, nor the Connaught with its much-modified Lea-Francis engine, in viewing the trend of cylinder layout, for they all use someone else’s engine for want of anything better or lack of means to design their own. On engine details trends can be viewed closely, for even if a racing car builder has to use a proprietary engine he can embody his own ideas in the detail work and thus contribute to the whole trend of design. Twin overhead camshafts to operate the valves are almost universal, being used by Ferrari (on the four-cylinder), Maserati, Osca, Gordini, Alta, A.F.M. and B.R.M., and the old design of Maserati as used by Platé. With the exception of Alta, who use chain drive, the camshafts are all driven by trains of spur gears, although the position of the drive varies from B.R.M. in the centre of the crankshaft to Alta at the back and the others at the front. In general the front location for the drive is the most favoured as this allows greater scope for driving accessories, such as magnetos, oil pumps, water pumps, fuel pumps, etc., from the same gears. Only Veritas and the 4-1/2-litre Ferrari retain single o.h.c. and neither of these can be said to be truly current designs. The remaining engines in use are all of pushrod o.h.v. layout more from availability than racing design and the proposed twin-overhead camshaft layout for the Bristol engines helps greatly to indicate that this type of layout is a must for a racing engine. A development that is gaining popularity is the use of two sparking plugs per cylinder and at present this is practised by Ferrari, Maserati and Alta, while magneto ignition would be universal if it was not for the B.R.M. Admittedly the Bristol-engined cars run on battery and coil, but this is again force of circumstances rather than racing design. How to drive the magnetos or where to put them is still open to doubt, for Ferrari began with one on the rear of each of his camshafts, only to move them to a joint mounting on the front of the engine, due to overheating of the windings. Maserati began with a single magneto at the front, driven from the camshaft drive intermediary gears and then supplemented this with a second magneto mounted on the rear of the exhaust camshaft. Connaughts moved theirs from an original forward position to a rearward one, while Gordini,  Osca and Alta mount theirs at the front and Platé to one side.

Gearboxes are to a certain extent governed in much the same way as engines, there being a great deal of apparent design which is in reality availability and adaptability. With the exception of B.R.M. and Veritas, who use five-speed gearboxes, most people are satisfied with four, but where to put them and how to operate them shows much diversity of opinion. The majority of people couple the gearbox direct onto the back of the engine, but Ferrari, Osca, B.R.M. and E.R.A. prefer to mount it in unit with the differential unit, thus leaving the cockpit very much clearer for the driver’s legs and the pedals. With the exception of Connaught and H.W.M., who use preselector gearboxes, the straight-forward type, either “crash” or synchromesh, is agreed upon. Operation of the gears follows no definite trend, the positioning of the lever depending on the layout of the gearbox selectors, space in the cockpit or chance. At the moment the most popular place for the gear-lever is in the centre of the cockpit, between the driver’s legs, and it is either vertical or cranked slightly to one side. B.R.M., Connaught, Osca, Cooper and Alta favour a right-hand change, Ferrari and E.R.A. a left-hand, and H.W.M. are alone in having the lever on the steering column. The day is indeed far off when a driver can drop into any racing car seat and automatically reach for a universally positioned gear-lever. Each racing car has its own little idiosyncrasy as regards the gear change and even cars using identical gearboxes show no conformity of layout. Coopers use a horizontal movement with the right hand, Frazer Nash a normal movement with right or left hand and E.R.A. a rather rearward though normal movement with the left hand, all using the Bristol close-ratio gearbox.

The drive from gearbox to rear wheels is, of course, largely dependent on the rear suspension layout, but the use of a straight prop.shaft line or the use of reduction gears is still equally divided. Ferrari, Frazer Nash, E.R.A., Osca, Alta, Platé and Cooper all run their prop.-shafts at axle level, while Connaught, Gordini, A.F.M., Veritas, Maserati, Aston-Butterworth and B.R.M. all use some form of reduction gearing to position the engine and transmission as low as possible. H.W.M. compromise by using a hypoid final drive. Of those who use a reduction gear in the transmission Gordini, A.F.M., Maserati and Veritas mount it in front of the differential, Connaught and Aston-Butterworth behind and B.R.M. break away entirely by doing their lowering at the power take-off point in the middle of the crankshaft. Generally speaking this lowering is done with a view to allowing the driver’s seat to be mounted lower, but E.R.A. have overcome this problem by seating the driver beside the transmission, all other cars having central seating positions.

On the question of chassis layout, design has a free hand, unhampered by the necessity of using proprietary parts and in such things as frames, front and rear suspensions, engine mountings, braking systems and wheels, fuel and oil tanks we can truly assess the trends of design and there is much of interest. Dealing first with the main chassis frame the general trend is for tubular construction, using two large (around 4 in. diameter) tubes as a basis. This type of frame is used by Ferrari, Gordini, Maserati, Osca, Platé, Connaught, Frazer Nash, H.W.M., Alta and E.R.A., although how the two tubes are placed relative to one another still depends on the individual designer. Ferrari, Gordini, Maserati, Osca, Platé, Frazer Nash, Alta and H.W.M. start with them parallel, while E.R.A. widen towards the rear and Connaught close in. The multi-tube or spaceframe layout, so popular among sports car builders, has yet to be taken up seriously by racing car designers, only A.F.M., Cisitalia and Veritas using true space-frames, though Cooper uses a version of this on the 1953 Formula II car. Ferrari, H.W.M. and Frazer Nash incorporate space-frame principles in strengthening their main frames. The Aston-Butterworth retains box-section side-members and the B.R.M. is unique, as in so many other design details, in using side-members built up from two small tubes one above the other spaced apart by steel sheet. E.R.A. break new ground in their frame design by the use of oval-section light-alloy tubing for their main frame. The mounting of the engine behind the driver has now been dropped completely and the more normal forward position is universal, although in this there are many variations. Exactly where to place the engine in relation to the centre line of the front wheels varies by as much as six to eight inches while B.R.M. mount their engine at an angle to allow the prop.-shaft to run beside the driving seat and Maserati set their engine a few inches to the left of the centre line of the car, the prop-shaft then running, at an angle, to the centrally-placed differential housing on the rear axle. This being in the interests of under-bonnet space for the accessories.

One of the most important features in the design of a racing car today is the suspension layout and every manufacturer has his own ideas on what is best.. Much of this opinion overlaps so that one can assess with reasonable accuracy the trend of suspension design and also whether the direction of the trend is sound. In front suspensions one thing is certain and that is, that independent suspension is a foregone conclusion and equally it is almost universally agreed that the i.f.s, shall be of the double-wishbone variety. That is to say that constant wheelbase is retained through the movement of the suspension, variation being in the track. How this movement is located and how the parts are manufactured vary greatly as do the controlling mediums. Gordini, Connaught. Ferrari, Maserati-Plate, Osca, Alta, Veritas, H.W.M., Maserati, A.F.M. and E.R.A. all use double wishbones, but their construction varies from forgings of A-shaped brackets as on the Maserati to welded A-brackets on the Connaught, and from single arm forgings on Gordini to a combination of single arm and A-brackets on the Maserati-Platés, but in all cases the basic principle of the movement is the same. Having reached agreement as to the best geometry for the front suspension, views on what to use as a springing medium follow no fixed ideas. Coil springs are as popular as anything, being used by H.W.M., Osca, E.R.A., Maserati, A.F.M. and the Platé cars; Connaught, Veritas and Gordini adhering to torsion bars while Ferrari is alone, in using a transverse leaf spring, as is Alta with rubber blocks in compression. The later Ferraris support this idea by using rubber in compression in conjunction with a very thin leaf spring. Although Ferrari alone uses a leaf spring with double wishbones, Cooper, Cisitalia, Frazer Nash and Aston-Butterworth also use this type of spring medium, but use the spring itself to form one of the wishbone members in a very simple form of suspension that has a similar geometry to the true double-wishbone layout. B.R.M. remain the sole supporters of the trailing link layout, whereby constant track is maintained at the expense of a variable wheelbase, and they are also alone in using air in compression as the springing medium. Taking all forms of i.f.s. into consideration double-wishbone layouts are definitely in vogue, while there is little to choose between coil springs and leaf-springs. At the rear of racing cars it is by no means a foregone conclusion that independent, or even semi-independent, is necessary, for at the close of the last season the undisputed Formula ll masters, the Ferraris, were exceedingly hard pressed by the new Maserati which has an old-fashioned one-piece axle, while in mid-season the Ferraris suffered their only defeat, at the hands of Gordini, again with a one-piece rear axle. One thing that is certain is that any form of rear suspension that is going to oust the conventional layout has got to be much more superior to succeed, whereas a mediocre i.f.s. can often prove better than a good beam-axle front end. It is perhaps for that reason that there are so many versions of the popular de Dion layout where each wheel moves independently to the other but the two are located to the chassis by a common member. This system is employed in varying degrees of technical merit by Ferrari, H.W.M., Osca, E.R.A., Connaught, B.R.M. and A.F.M., and though the theoretical results are similar, the practical ones differ greatly as do the springing mediums. H.W.M. and Connaught use torsion bars mounted parallel with the frame sidemembers, B.R.M. air in compression, E.R.A. and A.F.M. coil springs, Ferrari, transverse leaf spring and Osca 1/4-elliptic leaf springs. Of the one-piece non-independent axles Frazer Nash and Gordini use parallel torsion bars, while Maserati and Platé use splayed  1/4-elliptics. Cooper, Cisitalia and Aston-Butterworth use transverse leaf springs to form part of their i.r.s. in conjunction with a wishbone on each side and Alta has i.r.s. of a wishbone basis, using compressed rubber blocks. On numbers the de Dion system of rear end holds sway, but on results the good one-piece non-independent systems are not far behind.

All designers, builders, manufacturers or assemblers are agreed upon one thing and that is, the use of hydraulic brake operation. Most people support the two-leading shoe type of layout, but Connaught show a variation, using two-trailing shoe, while B.R.M. open new ground with “disc” brakes. In conjunction with hydraulic brakes, elektron drums are popular, using shrunk-in or riveted liners, while in this country the Al-fin bonded drum and liner is in great favour. Not everyone uses the conventional drum and Rudge splined hub, Alta and A.F.M. using drums integral with alloy wheels, and both these concerns use a non-standard method of fixing, Alta employing a knock-off type hub-cap with a wheel on a plain hub at the front and at the rear a similar arrangement with bolt heads inside the drum/wheel assembly locating in a slotted plate on the axle shaft. A.F.M. locate their alloy drum/wheel assembly by four studs, as do Frazer Nash and Veritas their pressed steel wheels. These are, of course, traced back to the B.M.W. ancestry of the three cars. Connaught, Cooper, E.R.A. and one of the Aston-Butterworths use alloy wheels bolted to the hub by studs and nuts, and this is an indication of the advances made in tyre design, for rarely does a Formula II car now have to change tyres during a race, so that the disadvantage of slow wheel removal is more than offset by the reduction in weight afforded by the bolt-on type. Ferrari, Maserati, Gordini, B.R.M., Osca, H.W.M. and Cisitalia all use the conventional wire spoke wheel on a Rudge hub with knock-off hub caps, Ferrari having experimented with hub caps with three ears against the normal two. Positioning of front brakes has shown no change from the conventional hub mounting, though Nardi-Danese have produced a vehicle with the drums on the outside of the front wheels, but it has yet to be raced. At the rear, however, ideas vary, H.W.M. and Osca using inboard mounting, with a drum on each side of the differential unit, while the rest conform to the normal practice of hub-mounted drums.

As regards fuel tanks and oil tanks, most engines being a the dry-sump type, only Connaught and E.R.A. have bothered to mount the tanks within the wheelbase. Other designers being content with tail-mounted tanks, supplemented by extra ones under the driving seat, as on the Gordini, or alongside the frame as on H.W.M., Veritas and Cooper. Ferrari and Maserati agree in keeping the oil tank as far from the engine as possible, mounting it in the extremity of the tail, while H.W.M. fit it under the seat, and Gordini under the driver’s feet. Connaught incorporate it in the front chassis crossmember and most Bristol-engined cars are wet-sump.

Lastly we come to the question of carburation and exhaust systems, both the items being closely allied to one another, and in these subjects there is a certain amount of agreement that is more than mere fashion, or copying, so it is for that reason that I have left the subject to the last. With the supercharged engine now almost extinct, great attention is being paid to gas flow in the unsupercharged engines and it is in connection with this that there are very definite design trends. However many cylinders are concerned, the aim nowadays is to treat each one as a separate engine and tune the inlet tract and the exhaust pipe in unison. This principle is by no means new in car racing, nor are any of its mysteries unsolved in the motor-cycle racing game, but its adoption almost universally in present-day racing Is a very definite trend. Closely coupled with this principle is the now almost universally used Weber carburetter, which, in racing form, enables each cylinder to have individual carburation. Ferrari, Maserati, Ogre, Platé, H.W.M., Alta, Veritas, A.F.M. and Gordini all use Weber carburetters with complete satisfaction. The most popular model is the DCO series which is a double-choke instrument with two sets of jets, chokes, throttles and adjustments, but housed in one body and using a common float chamber. This type is easily adapted to a pair of ports and as all racing engines of the present day have separate inlet ports to each cylinder the mono-cylinder gas flow theories can be applied easily. Using one DCO instrument to a pair of cylinders, Gordini, Maserati, Osca, Platé, H.W.M. and Whitehead’s Alta all make use of the single-cylinder theory. Ferrari appear to have a close liaison with Webers and for the four-cylinder Formula II car they have a model known as the DOE, which is a single-cylinder carburetter, there being one to each of the Ferrari cylinders. In all the cases mentioned the intakes are fitted with extensions, of varying lengths, depending on the port size, in search of free ram effect from the pressure waves existent in the inlet tract. Also following this theory, but using motor-cycle type carburetters, are Connaught and Cisitalia, the former using Amal and the latter del Orto carburetters. Connaught have probably done more experimental work on gas flow in inlet tracts than most people and though their result looks ungainly it is most effective. Geoffrey Taylor follows similar principles on the Alta, but using four S.U. carburetters. Other unsupercharged protagonists all suffer from siamesed ports of one type or another, so that different principles have to be employed, though the 4.4-litre Ferrari and the A.F.M. V8 use downdraught Weber carburetters, while the Bristol-engined cars retain the original Solex instruments. In getting the air to the carburetters there is a diversity of opinion, for Gordini, Maserati, Osca, Ferrari and Cisitalia cover up the space around the intakes, so that they draw from “still” air, while Connaught, Cooper, Frazer Nash, A.F.M. and 4-1/2-litre Ferrari employ scoops or deflectors to persuade the air to enter the carburetters. Having used the mixture in the engine the method of disposing of it varies greatly. H.W.M. were among the first to do away with the long exhaust pipe and fitted short stubs that protruded through the side of the bonnet, mainly with a view to reducing the number of breakages of tail-pipes that they had been experiencing. They found, however, that the short stubs could be used to an advantage to assist gas flow, in conjunction with ” tuned “inlet tracts, and their lead has now been followed by Ferrari, on the four-cylinder, Alta, Cisitalia, A.F.M., Frazer Nash, Veritas, E.R.A., Platé, and the Thinwall 4-1/2-litre Ferrari. Maserati, Gordini, Connaught, Cooper and Osca all retain long tail-pipes running to the rear of the car, but each has a different arrangement. Maserati has two pipes, one taking gases from the first three cylinders and the other from the second three. Gordini uses a six-branch manifold feeding into a single long pipe, Connaught have cylinders 1 and 4 coupled, and 2 and 3, joining the two manifolds together into a common tail-pipe, Cooper exhaust like Maserati, 1, 2, 4 3 into one pipe and 4, 5, 6 into another, while Osca connect each subsequent pair, taking them into a common expansion chamber with a single tail-pipe. Clearly exhaust gas flow is occupying much thought but no very definite conclusions appear to have been reached as yet.

Apart from such details as instrument board layouts, wheel and tyre sizes, fuels and fuel systems, that covers the main design trends in current International Grand Prix racing, and as that category is fast becoming a single group, namely unsupercharged 2-litre engines, we can view with a good deal of certainty the lines along whith future racing car design will run. 

We come finally to Formula lll, or 500-c.c. racing, wherein there is little pure design but a great deal of very ingenious improvisation or adaptation. With one or two yet-to-be-proved exceptions, the whole movement is agreed that maximum power is to be obtained at present from existing motor-cycle engines, and of these the single-cylinder Norton holds sway, though J.A.P. do their best to compete. Other units, such as Triumph, B.S.A., B.M.W., D.K.W., Gilera and Guzzi are used but with little or no success. On the question of the suitability of the modern close-ratio motor-cycle gearbox there is no dissention, nor on the advantages of chain drive. On the matter of engine position it is with one or two exceptions agreed that it should be behind the driver. Chassis design shows a greater divergence of opinion, although all-round independent suspension is fairly generally applied. At the front various layouts of the double-wishbone pattern are usual, and so many and so varied are the Formula III cars, especially in the “one-off ” group, that they would need a separate article to deal with them all fully. Suspension mediums at the front range from transverse leaf springs, as exemplified by Coopers, through air struts on the Grenville, to rubber in torsion on the Kieft. At the rear fully independent layouts are general, only one version of the Scampolo bothering with the added complication of de Dion. Double-wishbone layouts, or transverse leaf spring and wishbones, are popular, though the swing-axle style, as pioneered in this class by Iota and perfected by Kieft, is fast becoming popular. Here rubber strands in tension are becoming fashionable, and justifiably so, for they have the lightest weight and near-ideal characteristics. Chassis frames of the “space-frame” variety are produced in varying “one-off ” forms, as are the more conventional twin tube layouts, there being no definite trend towards either. In the same way the use of wire or cast wheels is still an open question, Cooper supporting cast wheels, Kieft light-alloy rimmed wire ones, though all are in accord on the lack of need of knock-off hubs. Rack-and-pinion steering is gaining in popularity and hydraulic brakes are universal, while on the subject of brake drums, Cooper retains them cast integral with the wheel and Kieft and J.B.S. use Al-fin drums on separate hubs. Design in Formula III is by no means stagnant but it is hampered a great deal by the cost of having special parts made, so that much of what appears to be design trend is in reality due to the availability of limited parts that can be adapted for racing.

That then is the present position of design among the chief contestants in International Formula racing and it can be boiled down, in the case of factory inspired pure racing-car design, to Formula II activities by three Italian firms, one French, one German and one English, ably supported by numerous other concerns who are making the best use of existing conditions.

American design for Indianapolis cars has not been brought into the discussion, as that is a branch of automobile engineering worthy of an article in itself, and is all concentrated on one track. Little of the knowledge gained being applicable to European road racing, it would only fog the issue to include it in an article confined essentially to classic road racing.—D. S. J.