Design discussion

In which the Editor extends some arguments contained in last month’s “Showdown” article

The idea was expressed in Motor Sport last month that enthusiasts who know about cars and drive them far and fast should eschew “vintage” designs and, by purchasing modern models for their daily motoring, set an example to the car-buying public of the benefits of such technical items as i.r.s., elimination of the propeller shaft, reduction of greasing points and so on.

Leaving out cars with front-wheel-drive, in which independent springing of the undriven back wheels is easy to achieve (or if for some reason it is ignored, merely means that a light axle beam is involved) and rear-engined cars in which i.r.s. is virtually forced upon the designer, there are the following front-engined/rear-drive cars the enlightened manufacturers of which provide independent suspension of the back wheels, for maximum riding and cornering efficiency on rough roads and the elimination of judder and wheelspin under acceleration which is a shortcoming to which rigid rear axles are prone, particularly when unlocated and attached to the chassis by leaf-springs:

A.C. Ace and Aceca .. Transverse leaf-spring and wishbones.
A.C. Greyhound .. Coil-springs and semi-trailing arms.
Fairthorpe (all models) .. Coil-springs and wishbones (swing axles optional on Electron).
Jaguar Mk. X .. Coil-springs, with lower wishbone, stressed articulated drive shafts.
Jaguar E-type .. Coil-springs, with lower wishbone, stressed articulated drive-shafts and anti-roll bar.
Lotus Elite .. Coil-spring struts, with stressed articulated drive-shafts.
Triumph Herald .. Transverse leaf-springs and swing axles.
T.V.R. .. Transverse torsion bars and trailing arms.

Mercedes-Benz (all models) .. Coil-springs and single joint low-pivot swing axles, with subsidiary coil compensating spring.
B.M.W. 1500 .. Coil-springs and trailing links.

Pontiac Tempest .. Coil-springs and swing axles. “Transaxle” curved propeller shaft.

Skoda (all models) .. Transverse leaf-spring and wishbones.

Those, then, are the cars you should go for, unless you decide that divorcing the engine from the driven wheels is ridiculous and prefer a car with front-wheel-drive or rear-engine location. Personally, based on satisfactory experience of the B.M.C. ADO15 and ADO50 designs, I vote for the former. Citroën, the World’s most advanced car, has had driven front wheels for nearly 30 years and the DS in its latest, more powerful form is a very fine motor car indeed; if ever it gets the air-cooled flat-six engine which rumour says its designer always intended for it, it will combine in one vehicle practically everything I find desirable. So enamoured have I become by the safety factors inherent in a front-wheel-driven car that I long for the day when Alec Issigonis will trigger off the next B.M.C. offering of that species. He, like the Citroën designer, has been obliged to use a conventional engine already in production.

You cannot tell me that the bulgy bonnet of the old torsion-bar sprung Morris Minor wasn’t intended to protect a flat-four engine, whereas Issigonis was prevailed upon to use an existing side-valve lump of iron when the car went into production. And while this talented designer has shown quite outstanding genius in placing another production B.M.C. engine across the front of his Mini to save space within the body envelope, I wonder whether, at all event in his dreams, Issigonis hadn’t visualised a flat-four, or even a swash-plate power unit, for these brilliantly conceived (if less conscientiously assembled) little cars? I suggest this it spite of Issigonis’ statement in the current issue of Road & Track that designing new engines as well as new cars is too big an undertaking for him to adopt it….

It remains to be seen whether B.M.C. can achieve the same success with larger versions of the ADO15 layout. Personally I believe they will, should their future policy lie in that direction despite rumours that nothing larger has followed the Minis because there is a limit to how much power can be used with f.w.d. without an excursion into the realms of dangerous handling characteristics, a theory that the Cooper-Minis go some way towards refuting and to which I do not subscribe. I would like to see Alec Issigonis, aided by rubber-man Alex Moulton, cock a snoot at Citroën with, say, a big trans-engine f.w.d. car powered by a 3-litre 6-cylinder B.M.C. engine, but whether a longer engine could be used across the car without seriously restricting the steering lock is open to conjecture.

Whether your choice is for front-drive, rear-engine or divorced power unit and axle in a car with all-round independent suspension, there is still great variety to be found in the technical approach of 1962. I was amused recently to read in Lord Montagu’s entertaining journal The Veteran and Vintage Magazine the statement that in 1898 “motor car design was in a state of flux: engines were placed in front, amidships, and at the rear some were horizontal, others vertical, while at least one—the Clement-Panhard—was slightly inclined.” The position is not so very different over sixty years later and inclination of the engine to secure a low bonnet line, as on the Mercedes-Benz 300SL, B.M.W. 1500, Chrysler Valiant, and Peugeot 404, for example (or a compact boot in the case of the rear-engined Simca 1000) has extended to the underfloor engines of the VW 1500 and the Fiat 500 Giardiniera in which the engine has been turned on its side, while the data on the opposite page show that cylinder disposition has by no means reached standardisation. Moreover, N.S.U. have their Wankel rotary engine as an extremely compact power unit of the near-future, and Rover and others are convinced that the gas-turbine will eventually have its day.

One aspect of engine design not yet exploited by British designers is that of smoothing out the 4-cylinder power unit and improving its durability by providing it with five crankshaft bearings, as adopted by Alfa Romeo, B.M.W., Chevy II, Facellia, Goggomobil, Simca and Volvo.