From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
'Autocar' magazine road test report for the 4¼-litre Bentley, detailing its performance, handling, and features.
| Identifier | ExFiles\Box 82\4\ scan0341 | |
| Date | 1st May 1936 guessed | |
| The Autocar Road Tests The new Bentley at Tyneham, in Dorset, during its test: this district near Wareham offers an entirely unspoilt coast line IT is not too much to say that, with the introduction of the 3½-litre Bentley some three years ago, a new standard of car values was set, for never previously had a car of similar size given so high a performance with such remarkable ease and quietness of running. The recent announcement that a bigger engine, of 4¼ litres, was to be made available instantly caused those who knew the 3½-litre to speculate upon the probable advantage, not so much from the point of view of sheer maximum speed, which already was satisfying enough, but from that of all-round performance, and acceleration in particular. The 4¼-litre Bentley, rated at 30 h.p., is now being delivered, and an example has been put through the usual exhaustive tests carried out by The Autocar, involving timed records of the performance figures at Brooklands track and over 400 miles of road driving under owner conditions. It is not easy to know where to start in apportioning full and proper credit to this altogether remarkable motor car. Analysed, its individual features show up exceedingly well, but it is as a whole that the car must be judged, and as one costing £1,500, backed, of course, as everyone knows, by the most famous firm of car manufacturers in the world. One cannot help feeling when handling this car that it represents the accumulated store of knowledge of that firm in high-class car production, put together to evolve a machine that shall meet every requirement of the most fastidious driver interested in performance—but refined performance. In a way it seems almost purposeless to go point by point through this car, and to say, for instance, that the steering is very good and the springing extremely comfortable, or that the brakes give exceptional power, since, in the eyes of the makers, these are nothing more than a car that satisfies their rigid standards must necessarily possess from the commencement. It is the combination of features, the manner in which one supports another, that gives the car an incomparable “feel.” Whilst the performance figures speak for themselves, the quality of the important top gear acceleration will be particularly observed. What is not apparent from cold figures is the fact that everything the car does is achieved with amazing ease and in a degree of quietness that approaches dead silence. Yet there is all the liveliness of a first-class sports car derivable from the engine, with hardly a hint of exhaust note, no fuss, no vibration, not even hiss from the twin carburetter intakes. An exhaust cut-out is no longer fitted, by the way. This car can be driven almost entirely on two gears—first or second for starting, and top for most of the time in ordinary running, so flexible is the engine and so much silky power does it give even at low speeds. On the other hand, a really quick getaway can be achieved, and second and third gears provide an exhilarating performance. Second is so quiet as not to be noticed until nearing the limit on that ratio; third is literally indistinguishable from top, and at lower speeds one may go to change down from top only to find that third is already engaged. Passengers are certainly unable to detect the difference. A right-hand lever, working in a gate and with the very best form of synchromesh on top and third, provides the most highly developed lever change that has yet appeared on a car. The action is beautifully balanced, and the gears go in imperceptibly. From second up to third and from third to top, also down from top to third, in which the synchromesh operates, changes can be made as rapidly as the lever can be moved. It is almost as though the car had two top gears. Rushing acceleration is given on third, yet the engine remains entirely soft, and the evidence of the speedometer is hard to believe. Even more notable is the acceleration on top gear from around 50 m.p.h., there being a great reserve from that middle range onwards which quickly sends the speedometer needle soaring towards the 80 mark. It is a wonderful experience to handle this car over main roads which give opportunities for employing the performance. The throttle goes down, and the speedometer needle sweeps round the dial; the landscape rushes past, but nothing else emphasises the rate of travel, and conversation in a normal voice can be continued. In favourable conditions it is only the will of the driver and the nature of the road that decide the speed, up to a figure within close reach of 100 m.p.h. The whole running is so exceptionally easy, even to a seasoned driver acquainted with the best fast cars there are, that speeds up to 70 m.p.h. are automatically used. Within this range the car almost takes itself along, the driver not having to concentrate upon his handling of it. Conditions at Brooklands for these speed tests were not actually adverse, but were new to the car. With all this performance, it is a characteristic that the car feels eminently safe. The driving position and all the controls are admirably arranged, whilst vision is all that can be desired. Also, there is a surprising feeling of compactness, so that the car is easy to handle. The steering allows the driver to put it exactly where he wishes; the springing is controllable in accordance with the road surface, and load by means of a finger-operated control at the centre of the spoked steering wheel. This regulates the damping provided by the special hydraulic shock absorbers. Even at the maximum position of the absorber control there is no actual harshness about the suspension, and the comfort afforded in the back seats as well as in the front is exceptionally good. The braking system embodies the Rolls-Royce mechanical servo, driven from the gear box and assisting the action, so that light pedal pressure is intensified and extremely powerful braking applied to the wheels. They are extraordinary brakes, smooth to the last degree, but relentless in their power to pull the speed of the car down, and they afford the uttermost confidence. The steering mechanism is quite high geared, 2¾ turns of the wheel giving the full lock-to-lock movement, but the balance between lightness for ease of control and accuracy for safe steering at speed has been exceptionally well struck. At no time is more than the mildest amount of road wheel movement felt through the steering, whilst the caster action to return the front wheels after a corner is just right. Unusually good steering lock is provided. The average speed capabilities are, of course, altogether beyond the ordinary, and a long day’s run leaves the driver not only fresh but willing to go on still farther. Most ordinary climbing is carried out swiftly on top, and third will deal with almost any gradient on main roads. It is interesting, too, as showing another side of the car, that a narrow hill with a maximum gradient of 1 in 4¾, and an awkward “S” turn, which until recently was an observed test in one of the classic trials, but which now has a good surface, was climbed with the greatest of ease, with a full load on board. There is hardly a tremor from the engine, even when accelerating from crawling speeds on top gear; it can, however, be felt a little when ticking over with the car stationary unless the ignition Noteworthy features of the underbonnet compartment are, first, the beautifully finished engine, and the very big air cleaner and carburetter intake silencer, the snap catch oil filler, and the secure yet neat mounting of the wheel tools. | ||