Fuel consumption crucial

Press, Volume CXIII, Issue 33252, 15 June 1973, Page 6

Fuel consumption crucial

Better fuel consumption is likely to become the prime target for car engine designers, because of the world’s developing energy crisis. It will certainly loom large in the development of four new power units which British Leyland is expected to announce in the next few years. One question this raises is the future of the Wankel type rotary engine, which, in spite of its other merits, has so far proved notoriously thirsty, John Langley reports in the "Daily Telegraph.” There is already talk in the United States about the possibility of petrol rationing. The American Government has announced plans for cultivating a “conservation ethic” and issued a list of “thrift measures,’ ranging from cutting speeds on the motorways to the formation of car pools. Anyone who imagines that this is just another example of American hysteria that will have no effect in other countries could be wildly wrong. Some people in the oil industry believe a similar slow-down in the use of oil products will be needed in Britain, not in 15 years but in five. While there is no suggestion yet of actual petrol rationing, there is talk of creating opinion that would discourage the wasteful use of petrol. And one of the first targets, by a happy accident for town planners, would be the car commuter. By exhortation, tougher

parking controls and possibly the introduction of road-pricing techniques, car owners would be "encouraged” to switch to an improved public transport system instead of driving to work every day. Sharp increases in petrol prices over the next few years are in any case likely to help to bring this about. There are also suggestions that changes in the tax laws may be needed to make the use of company cars less attractive. Petrol is likely to become substantially more expensive as producers seek a higher return for their diminishing natural resources, and because of the high cost of developing alternative sources of oil. As for the new Leyland engines, all Lord Stokes has said is that they will be of

an exciting specification and will incorporate increased amounts of aluminium. as an aid in meeting exhaust pollution laws. The main advantages of aluminium are better heat dissipation and weight reduction —a significant factor where larger capacity engines are needed to maintain the performance from detuned “clean” power units. Heavier engines are not only a disadvantage in themselves but also require uprated suspensions, engine mounts and so on, adding to cost and increasing the petrol consumption. One of the engine designer’s current dilemmas is that “detoxing” equipment is having an adverse effect on petrol consumption. The hope must be that more efficient basic designs can be evolved to

give both cleaner exhausts and better economy. One hopeful sign is that Leyland engineers have had considerable success in borrowing from racing-car practice a multi - valve cylinder head for adapting one of their existing overhead camshaft engines. A car fitted with this interesting new engine will be announced soon, and promises an unusually good combination of performance and economy. The principle could be applied to other engines. It is, perhaps, most fortunate for British Leyland that it did not get involved with the Wankel engine, even though it has been keeping a close watch on its competitors’ efforts in the rotary field. The Wankel’s fuel consumption is about 20 per cent heavier than the conventional piston engine’s, and is now its major disadvantage. Companies as eminent as General Motors and Mer-cedes-Benz are said to be trying to solve the problem by developing a stratified charge Wankel with direct fuel injection, but at present the cost of the refinements would be prohibitive in mass production, particularly as the basic Wankel has not lived up to its promise of being cheaper to make. With the prospect of steadily rising fuel costs and greater restrictions on use, some people are openly questioning whether there is any long-term future for the car. The motor industry’s faith is that the desire for personal mobility is now so deep-seated that people will still want their cars, even if they cannot use them as freely as before. And increasing affluence will take care of the cost element. But with so many imponderables on the horizon, it will be even more crucial for manufacturers to find the right answers when planning the cars of the future. It is significant that British Leyland has just appointed Mr Charles Bulmer, the former editor of “Motor,” to advise it on long-term product planning, and the sort of cars and engines that are likely to be needed in 10 years’ time, Langley writes.