CARS IN 1975 THE CHANGES AHEAD

Press, Volume CIX, Issue 31907, 7 February 1969, Page 9

CARS IN 1975 THE CHANGES AHEAD

(Specially written for "The

Press’’ by

A.J. PETRE)

A SURVEY of car design, manufacturing and merchandising trends suggests that the car of 1973 will not be vastly different from the car of today, but it will be more sophisticated, more comfortable, ! more reliable, a better performer. and almost certainly more expensive. Future developments can be divided into these main categories: engines, transmissions, body-shells, and suspensions.

Considering engines first: there seems no reason why the conventional reciprocat- ' ing-piston internal combustion petrol engine should not continue to be the main type of automotive power-plant for many years to come. The reciprocating engine is very far from being at the end of its development, and even the air-pollution regulations are unlikely to pose any threat to the reciprocating engine’s continued reign These regulations have, however, encouraged interest in steam, electric and gasturbine engines. Basically the position at the end of 1968 was that steam engines still (required much development Ito make them acceptable, and [they were still just as expen- | sive as ordinary engines, if not more so.

Although the steam engine has come a long way since the first steam cars, it would be hard to convince buyers they should favour an expensive unit that can have problems in cold climates, takes up to 30 seconds to start in the best conditions, and requires comparatively frequent replenishment of water. Against this must be set the silence, economy, and long life" of steam engines. The electric engine has even less to recommend it than the steam engine at the present stage of development. It requires heavy and very expensive batteries, which must be recharged frequently and replaced often, it produces comparatively small amounts of power, and an installation is no cheaper than a conventional engine. One British firm said it could sell electric “city cars” for about the same price as a Mini-Minor or a Ford Escort—but only if it could sell them in similar numbers and thus take advantages of the economies of large production. GAS TURBINE

The gas turbine engine also suffers from the penalties of expense and weight, and a gas turbine engine for cars seems even further away now than it did two years ago. At the same time, however, gas turbine engines for trucks are very close: the first production gas-turbine truck is scheduled to come off Leyland assembly lines in a few months. Then there are the rotarypiston engines, exemplified by the N.S.U.-Wankel engine overseas, and by the Walker unit in New Zealand. There are already Wankelengined cars in production, the main ones being the Japanese Mazda, and the N.S.U. Ro 80 saloon, which is a luxury model. Both have been praised by road-testers overseas, and it seems the rotary-piston engine could make inroads into the conventional engine market. The rotary engine is, in fact, the only alternative power unit that shows real signs of so doing. Even then it has some disadvantages: cost is about the same as for a conventional engine, and air pollution problems are greater because of the difficulty of achieving a perfect seal between the tips of the rotor and the side-wall of the casing.

DARK HORSE On the local scene, the Walker engine is at present a dark horse. Whether it will succeed cannot be judged until a full-sized power unit has been built and tested, but reports are certainly hopeful. We must wait and see. What changes are likely in the normal piston engine in the next few years, in the face of this competition? Undoubtedly efforts will be made to achieve better combustion of fuel, and hence better fuel economy and less air pollution.

It is also to be hoped that manufacturers will make more efforts to design a longer life into engines. Many of the smaller power units, in particular, wear out far too lyOverhead Camshafts Certainly more designers will follow the trend towards overhead camshafts. It seems likely that the low-mounted camshaft, operating valves by pusbrods, will soon disappear, just as the side-valve engine has disappeared. Fuel injection seems certain to gain more adherents, but cheaper installations will have to come first. This is another example of the economics of the motor industry: the more cars that use fuel injection, the cheaper the units will become.

Efforts will continue to make engines quieter, smoother more efficient and more powerful, and manufacturers are likely to turn to more cylinders as the easiest way of achieving this end. Small six-cylinder units and VB’s are likely to become more common, but there will always be a place for a smooth, reliable four-cylin-der.

In spite of punitive enginecapacity taxes by some Governments, engine sizes will certainly continue to increase in line with customer demands for more power and smoothness. There seems to be a move away from the highly-stressed high-reving small engine almost universal a few years ago. Engine manufacturers also have to face exhaust-noise regulations, but for most will be little problem, as their exhaust systems already reduce noise to well within legal limits. (To be concluded)