EVEN with the increased efficiency of modern cars, 100 m.p.h. is a rare performance. One hundred ni.p.h. from a standard production car of less than 2-litres engine capacity is still rarer. Narrow the qualification to an IIIISlipeTcharged car, of British make, and one's

choice is becoming limited. Mr. J. R. Stopford, however, is the fortunate possessor of such a machine, and his car is a 2-litre Speed Model Aston-Martin.

Whatever is or is not a sports-car, there is no doubt that the Speed Model AstonMartin deserves the epithet. It is obviously a machine designed to give an enthusiastic owner the greatest joy out of motoring. ' In such a car, the journey is of relatively small importance, and what matters is the manlier in which the journey is accomplished.

Actually I have referred to a standard production car, and Mr. Stopford's car, in which he was kind enough to give me a test run recently, is certainly quite standard as regards engine and chassis. It has, however, a modified two-seat( r body, with a nicely rounded tail, instev.d of the standard body, where there is a large luggage space behind the seats.

On Mr. Stopford's car there is still adequate luggage space behind the seats, except for those who like to travel AN ith all their household goods in attendance, and the spare wheel is concealed inside the tail, whereas on the standard body it is mounted outside. The special body also has cycle wings, without running boards. There are few cars which give one quite such a zest for the open road when one first gets into them, whether as driver or passenger. The big-24itre four-cylinder engine has just that degree of harshness about it which sports-car enthusiasts love. It is not rough, but one can feel all the cylinders working hard in a most

satisfactory manner. Even the fact that there is a certain amount of pinking at low speeds is no detriment to the knowing driver.

The compression ratio is 8.3 to I, and Mr. Stopford usually uses a one-third proportion of benzole in the fuel, although this is not absolutely necessary, with a clean engine. At the time when the car was tested, it had covered some 0,300 miles since brand new, and the engine had not been taken down during that period. This makes its performance all the more remarkable, for a high-compression sportsear as a rule needs more frequent atten tion. Certainly the engine, even after this big mileage, showed no signs of needing decarbonisation, which would lead to the fact that the cylinder head design must be extremely efficient,

The gear ratios are 11.38 to 1 first,. 8.33 to 1 second, 6.11 to 1 third, and 4.4. to 1 top. This gives comfortable maximum speeds on the respective lower gears of 40, 54, and 75 m.p.h. Top gear is essentially an open road ratio, though the engine runs up so well on the indirect gears that there is no lack of flexibility. It merely means that one uses second aud third where most ordinary cars would be in top. Seventy m.p.h. in third gear conies quite naturally, and this gear is most useful in traffic conditions such as one meets on a run out of London. The car has a pleasant bark from the exhaust, but is not unduly noisy, even at

high speed. When the engine is cold. there is a certain amount of piston noise, but it is well known that a tight engine may purr noiselessly, but does not deliver the horse-power. Again, therefore, the feeling of a true sports-car is enhanced.

Although a car of this type is able to exert a pleasant mastery over traffic, one cannot use its performance to the full except on deserted roads. I once made a remark in this paper that even readers of MOTOR SPORT might be surprised at speeds of over 100 m.p.h. on the road, but this proved so singularly incorrect, and there was such a galaxy of drivers who regarded it as a mere crawl, that one can speak with more confidence. However, I still stick to the remark that there are few cars which will top the " 100" in any case, and that even with these cars one must choose the spot with care. I suppose now that someone will shamelessly say he has done " 100 " in the middle of London I

Mr. Stopford. and I, as reasonably law-abiding motorists, were making for one of the fastest and most deserted roads which we know, a road which, I am told, sub rosa, is one where the police themselves test out their rapid machines. As a clue to its whereabouts, one may add that one sometimes meets Cambridge undergraduates travelling at very high speed thereon.

When we reached the best part of this road, where the telegraph poles stretch into the distance, there was a cross-wind, slightly in our favour, but, as against this, in the most favourable direction of the road there is a slight uphill slope. The first time we essayed a maximum speed test, we reached 98 m.p.h. The road is somewhat narrow, despite its straightness, and not over smooth, but the AstonMartin, even with the cross-wind, sat

down beautifully. It was a travelling example of the saying that a sports-car is safer than other cars. As a roundabout, built since I last used the road, hove unexpectedly in sight, I applied the hydraulically operated brakes, and the car slowed from its high rate of

knots rapidly and smoothly. I did a nice flick change into third, and essayed the same into second, but nearly missed it, much to the amusement of Mr. Stopford. He then pointed out to me that the lever was a little stiff to move across the gate, which sometimes upsets one's calculations in moving across from third to second. Thus warned, I accomplished the next change clown successfully, but I still regard that particular change, maybe on that particular car, as a little tricky until one gets used to it. We were disappointed at not reaching the " 100," and when we got to the fast stretch on the return journey, we tried again. Against the wind we could not do more than 93 m.p.h., however, so we turned round, Mr. Stopford vacated his seat, and I took the revs higher on the lower gears on the approach. Fifty m.p.h. appeared on the clock in second, and 75 m.p.h. in third, and I crouched

behind the aero screen. The needle flickered up towards the "100," the wind screamed by, and the car seemed to be going much faster than before. It passed the " 100" on the crest of the slope, and went on to 102 m.p.h.

Unfortunately I had no opportunity to test the accuracy of the speedometer, but from a considerable experience of such speeds I would be prepared to state that it was not far out.

It is most important to note, however, that on rather a cold day the temperatures both of water and oil were far lower than those which would give the most efficient running. The water temperature would not rise above 55°C., while it was only after the most prolonged high speed that we could get the oil thermometer needle to move at all, and it never passed the 42°C. mark. On a hot day in the summer, with the water temperature at about 90°, and the oil about twice as hot as it was during out test, even greater speeds would be possible, especially with the engine free

of carbon, and with. detail adjustments. It must be remembered it had not been touched on this occasion.

We did not try any acceleration figures, chiefly because the high gears are not suited to standing start attempts, and the results would be misleading for so high spirited a car, evolved for fast road work over long distances rather than for speed trial performance. One can, if desired, run at about 25 m.p.h. in top gear, but for all normal purposes one would use third or second gears for such a speed. We were using Champion R 11 plugs, but there was no trace of oiling up. As a matter of fact, I had just remarked on this feature when

a cylinder cut out. Somewhat crestfallen, we opened the bonnet, and found a plug terminal had jumped off 1 A Scintilla Vertex magneto is fitted as standard, and all the electrical equipment is Scintilla. Petrol consumption works out at about 19 m.p.g. for normal running, neither travelling very fast nor consciously

loitering. On a fast car the figure is naturally variable, according to the run.

The Speed Model Aston-Martin is an admirable compromise between a racingcar and a touring machine, which, after all, is exactly what one means when one talks about " a sports-car."