With a performance to satisfy the most critical speedman, coupled with a degree of flexibility unusual in a sports car, the 1926 three-litre speed model Bentley shows a distinct improvement over the very fine sports automobiles that have hitherto left the Cricklewood works. Not only is the new car faster by some 10 m.p.h. than the 1925 type, but acceleration has been improved, while the brakes are still more efficient than of yore.

It will be recalled that the Bentley engine is of the four-cylinder type, of 80 mm. bore and 149 mm. stroke. Four valves are provided per cylinder, all operated from one overhead camshaft. The chief points of difference between next year's and this year's models are that the compression ratio has been raised, the piston crown is now of a different shape a redesigned camshaft is used, whilst slight modifications have been carried out in the valve gear in order to get lighter parts without any sacrifice of strength or reliability.

That the improved performance is solely attributable to the greater power obtained from the engine is proved by the fact that the car tested had exactly the same gear ratios, and weighed within a few pounds, the same as the previous model tried.

Commencing with some speed tests at Brooklands, we very soon found that the speed of the vehicle had been increased. Some half-a-dozen laps "all out" were indulged in so as to warm up the engine to the most efficient temperature. The day was so cold, however, that it was not until the greater part of the radiator had been blanked off by tying a handkerchief across the front that the most efficient temperature was reached; it was interesting to observe that the speed increased by some 6 m.p.h. so soon as the water in the cooling system became hot enough. Unfortunately, a fairly strong wind blowing against the car militated against the attainment of its maximum speed down the Railway Straight. Nevertheless, the half-mile was covered in 20.8 secs., equivalent to 86.54 m.p.h. Once in the shelter of the Byfleet Banking, however, a genuine 90 m.p.h. was reached and held. It should be mentioned that the car was in full touring trim with wings, windscreen, etc. A complete lap was accomplished in 1 min. 58 4/5 secs., equivalent to an average speed of 83.84 m.p.h. over the 2 3/4 miles. The test hill was afterwards climbed in 3 1/3 secs., equivalent to 18.19 m.p.h.

These tests were quite sufficient to show that the maximum speed of the 1926 model has been appreciably increased, but in order to convince ourselves that; the increased speed was not offset by any disadvantages or attained at a sacrifice of any of the flexibility or slow-running which have always been characteristics of the car, we continued our test over a couple of days under ordinary touring conditions.

Even if one leaves the question of the high compression ratio and the high gear out of consideration, the Bentley may be described as docile in traffic. With the ignition fully retarded it will crawl on its top gear of 3.78 to 1 at as low a speed as 7 m.p.h. However, the enthusiastic driver would invariably change down before the speed dropped as low as this. Third gear is only 5.03 to 1 and second gear 6.18 to 1, so that if, in traffic, one is brought almost to a standstill behind a slow-moving vehicle, a quicker get-away is assured by a drop straight from top to second gear.

The combination of a well-designed gearbox and very close ratios enables perfectly silent changes to be made up or down, with none of those irritating pauses in neutral which mark gear changes or the average touring car. Indeed, changing from second to third at low speeds, the lever is slipped through the gate as quickly as it is possible to do so, while one can attain the maximum speed on third gear-76 m.p.h. - and change straight into top without waiting.

Even without making the best use of the gearbox really high average speeds can he maintained without violating any of the written or unwritten rules of the road. It would perhaps, be unwise to give any figures, but we can safely say that it is perfectly easy to average 40 m.p.h. or more from London to, say Bournemouth without ever driving fast through inhabited areas, while, including the inevitable reductions to half speed necessary when meeting or overtaking other traffic, the. driver would he able to cover the distance of 12 miles in 13 minutes, assuming, of course that a reasonably straight road were used.

Although the engine is in all respects a standard 1926 power unit, the particular car we tried had been driven in the 24-hour race at Le Mans last June. The suspension was therefore stiffened by the binding of the springs with cord, while the Hartford shock absorbers were tightened to such a degree that the faster one went the more comfortable was the car. At 83 m.p.h., for instance, with four up, the comfort was all that could be desired, while the car held the road so steadily that it was not in the least tiring to drive at this speed. Dropping to a relatively modest 65 m.p.h., one had the impression that this was the car's comfortable cruising speed. At 40 m.p.h., the accelerator pedal was scarcely depressed, while the car burbled along in an irreproachable manner.

It is of course, essential that such speed capabilities should be associated with the provision of very efficient four-wheel brakes. Those on the Bentley, made under the Bentley-Perrot patents, are not only amongst the smoothest and safest we have tested, but are distinctly more powerful than on the 1925 model. At 30 m.p.h., for example it is possible to bring the car to a complete standstill in 24 ft., well under two car-lengths. From 10 m.p.h. the car can be stopped in a bonnet length - 3 ft. 6 ins. From 20 m.p.h. it can be brought to a standstill in less than its own length, while from the higher speeds of 40 m.p.h., 50 m.p.h., 60 m.p.h. and 70 m.p.h. it can be stopped in 51, 77, 143 and 223 foot respectively.

Now it is a very cruel thing suddenly to depress the accelerator pedal of a car as highly geared as the Bentley speed model when it is only crawling at 10 m.p.h. on top gear. Nevertheless, in order to bring rhe acceleration test into line with those of ordinary touring cars we have tried, we measured the acceleration from 10 m.p.h. on top gear. It will be observed that 30 m.p.h. was readied in 12 secs., 40 m.p.h. in 18 2/6 secs., and 50 m.p.h. in 25 1/3 secs. It took only 38 2/5 secs. to attain 70 m.p.h., while 80 m.p.h. was reached in 52 4/5 secs.

The control of the car is light and easy at all speeds, and steering is accurate to the proverbial hair's breadth. Starting is normally very easy, although on the car we tried the battery was somewhat below par owing to the car having been left standing with the lights switched on for long periods after dark.

In a word, the speed model Bentley can he described as a thoroughbred from radiator to tail lamp. It has that reserve of power and speed which enables it to be driven for 99 per cent of its life well within its capabilities, thus assuring long life and reliability of all working parts. Its instant responsiveness to a touch of the accelerator or brake pedal, its very high speeds on the indirect gears and the entire absence of mechanical noises of any description make the handling of it. sheer joy to the enthusiastic motorist. At the same time it calls for no special skill in driving.

The makers are Bentley Motors Ltd., Oxgate Lane and Edgware Road, Cricklewood, N.W.2. with showrooms at 3, Hanover Court, Hanover Street, London, W.1.