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Safety with exhilaration: the new Jensen

From Britain comes a revolutionary high-performance car with four-wheel drive and brakes that will not lock up on slippery surfaces

Everybody talks about automotive safety, and in the last decade the manufacturers have done something about it—they have installed seat belts, padded dashboards, removed or redesigned some of the lethal interior projections, and have made door locks more secure—but, by and large, they have been cautious about trying to sell safety. As they are all aware, Ford tried diligently in 1956, and the result was negative. The idea of safety not only was not exciting—it seemed loaded with potential backlash in that it got the customer thinking about such unpleasant things as crashes and contusions. What the safety movement needed was a more secure car that also promised more varied and satisfying driving.

That is what it got the other day when a relatively small British firm, Jensen, displayed at the London Motor Show the first four-wheel-drive touring car ever produced. Jensen has been in the business of building a classy line of sporting cars since before World War II. To say now that the Jensen FF, which is what its spectacular new car is called, made motoring history would not be an overstatement. The Jensen performs brilliantly, and it is also the safest car in the world. On a surface as slippery as soap it can roll to a smooth halt. More important, it can be steered even at cruising speed on such a surface—a virtual impossibility for a car with two-wheel drive except at very low speed. It is equally impressive on ice, snow, mud or sand. The visions of motoring off the road that this conjures up must make the mind of any copywriter boggle. Show an FF a hill in winter, and it will show you its stern. Watch it go round a corner on ice, and the chances are that the only thing that will keep you from buying one is the current price: ¬£4,343 or $12,160.

Jensens have never been cheap, so there have never been many of them, but they have always had a reputation for novelty. Richard and Alan Jensen, brothers of Danish descent who founded the firm in the early '30s at West Bromwich in the English Midlands, started by building stylish bodies around the engines and chassis of other manufacturers. Currently the firm produces only five normal-drive Jensen cars a week. Each is a painstaking production. Jensen customers (one was the late Clark Gable) "are very special people," explains a director.

Jensen has pioneered the use of big engines with cars of very low weight. The company went to safety belts long ago, and was one of the first to incorporate disc brakes in its vehicles. Now Jensen finds itself right in the forefront again with a concept so revolutionary that it has taken 15 years for it to be adopted at all. The secret of the new car lies in the installation within it of the Ferguson racing car four-wheel-drive system, a cherished dream of the late Irish tractor millionaire Harry Ferguson, and a Dunlop Maxaret braking unit. Neither has been used on a production car before.

The history of the Ferguson invention stretches back to prewar days, when Ferguson envisaged, with a racing motorist called Freddie Dixon, the possibility of building a racing car with four-wheel drive. The thought then was more dreamy than practical. Ferguson was preoccupied with his tractors, but Dixon set about designing a car that he could race and could also use to establish a land-speed record. He was joined in time by Tony Rolt, another racing driver, and by 1946 the pair had traveled well beyond the original idea of a racing car to the concept of an advanced passenger vehicle.

Four years later, in 1950, the two were desperate for additional brains and money but, fortunately, Harry Ferguson was at last free to provide the backing of his own mind and money. The Harry Ferguson Research organization was founded, and by about 1960, the year Ferguson died, much of the motor industry actually had accepted the four-wheel idea but insisted it was "not practicable in terms of cost." What helped pull many over the first hurdle was a privately made, independently witnessed documentary film. This compared the performance of a prototype vehicle fitted with the Ferguson Formula and Maxaret braking with that of ordinary cars. It is still a whispered legend in the trade.

In the film, the Ferguson car is shown quite clearly outperforming conventional vehicles of the time over atrocious surface conditions. The climax comes when the Ferguson races another car round a circular slippery track. As the driver in the conventional vehicle attempts to prevent the Ferguson from lapping him, he goes into an ignominious spin. "It has taken us all the time since then," says Rolt, "to show the industry that the idea is practicable. The Jensen will prove it."

Of course, four-wheel-drive vehicles are not new. They have been used for cross-country and military work, but their mechanization has been clumsy and their use of fuel and tires extravagant. On normal roads they convert to two-wheel drive but then carry around a great deal of weight which is not working. The Ferguson-type car, in contrast, does not use more gasoline than normal nor wear tires excessively. Its essential apparatus is a simple one. What the Ferguson designers did was to place a master differential between the differentials operating at the front and rear wheels. The result is that the front pair can turn faster than the back pair and vice versa. They act with one another, in other words, and not against.

The master differential gave Ferguson the opportunity to provide a car with perfect braking, i.e., one which will not lock up. Fitting a Maxaret brake (in use in aircraft since 1952) to all four wheels of a car is not only impractica but extremely expensive. Ferguson found a way to work all four brakes off one Maxaret by applying it to the master differential. This means that when one brakes hard in the Jensen the pressure is turned on and off many more times than could be achieved by what is known as cadence braking by the driver's foot.

To demonstrate their ideas in competition, the Ferguson Research people in 1961 raced a Grand Prix car in Britain. It won a major race while competing for the third time. Driven by Stirling Moss, the car beat a powerful field of BRMs, Coopers and Lotuses in the 165-mile International Gold Cup at Oulton Park in Cheshire. With this vehicle Moss was able to demonstrate clearly one of the most salient advantages of four-wheel drive. On high-speed corners it had no tendency to break away at the front or rear. Instead it would only drift out while maintaining an arc round the bend. All that was needed to pull it in was to lift the foot off the throttle. "The Ferguson," commented Moss at the time, "is more stable than anything I've ever experienced. It is good in the wet and the dry. In both conditions you can put your foot down harder. You can decelerate later and accelerate longer."

Tony Rolt (Freddie Dixon died a few years ago) now believes that the time of a Ferguson avalanche is near. "It is no longer," he explains, "a question of asking if it can be done, but of deciding when to start doing it." It has been estimated the additional cost to the consumer in the case of a mass-produced vehicle would only amount to 5% and that would eventually cover the retooling expense.

Jensen has no regrets over its own heavy research investment and subsequent tooling expenditures on the FF—$16 million. "People are slow to accept things," says the firm's Brian Owen. "Somebody's got to show it's safer. We are doing that." Under the direction of the firm's 38-year-old chief engineer, Kevin Beattie, they have used the Jensen four-seater C-V8 Mark III, which was introduced in the early summer of this year, as the basis of the FF. The two cars, long and rakish, are virtually indistinguishable in appearance and are powered by the same 6.2-liter Chrysler V-8 engine.

"What we set out to do," says Beattie, "was to make the safest car we knew how." To this end, over a period of 18 months and many thousands of miles of driving, extensive braking and transmission tests have been carried out.

Few people have, as yet, driven the FF, simply because up until a short time ago only two existed. Nevertheless, certain facts are indisputable. The FF will perform as well and in some areas better than, for example, the C-V8, which can reach a top speed of better than 140 mph and cover a quarter mile from a standing start in 15.5 seconds. "People who have driven it say it's fab," says Brian Owen. But more important to the industry and to anyone who drives cars is what Kevin Beattie said the other day in his dry engineer's language: "The system will provide controllability as long as sufficient friction to obtain any steering response exists between the tires and the road." That's fab.


CUTAWAY VIEW of the Jensen FF reveals, in circled area, the master differential and Maxaret antilock braking assembly that is its essential novelty. Four-wheel drive provides superb traction, and master differential permits front and rear pairs of wheels to revolve at different speeds as dictated by road conditions. Maxaret keeps brakes from locking—long a danger on slick roads.