Sporting Cars on Road & Track

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in Cars on Pout &Track

By Op GA Tiro fflo THE AMILCAR,

NAMED the Grand Sports, the Amilcar which we took out for a trial spin the other day, had all the qualifications which the most exacting would desire to find in a sports car. Asked to state what, in our mind, appeared to be its outstanding characteristic, we should reply : its controllability, which made itself evident at all speeds and on all kinds of road surfaces. As it so happened, the conditions were, on the whole, unfavourable. of which we were glad, since it made our test all the more interesting. We tried all kinds of stunts with it, accelerating and braking in circumstances which, in many cases, would have got us into very severe trouble, yet all the time we had the car under entire control. As an indication of its braking and speed capabilities—on the highways—we may say that we brought the speed down from 69 miles per hour to nil in less than 50 yards.

The leather upholstery well matched the grey coloured coachwork. The facia board, of aluminium, is remarkably well equipped, and is surmounted by a pair of windscreens arranged to form a V. There is ample room in the tail of the body for luggage but, of course, no dickey is embodied in this model. We have no hesitation in stating that the general appearance of the car, its lines, and the general design of its bodywork, are such as will please the most critical. Turning now to a more detailed consideration of the specification of the chassis, starting with the engine, and doing so happened in our case after a successful trial run, we were, on lifting the bonnet, immediately surprised at the apparent lack of material there. The

road performance of the car certainly gave us the impression that we were sitting behind an engine of at least II h.p., and it was no small surprise to us to discover that actually, we had been carried along by a monster of 1,074 c.c., derived from an engine having four cylinders each of 6o mm. diameter and 95 mm. stroke, giving a horse power, according to Treasury • and R.A.C. rating, of no more than 8.9

The valves are of the side by side type, and not overhead, as is most often the case with sports model engines. No cotters are used to support the springs, but instead, each spring rests upon a nut which may be best described as a shoe nut, and this again is backed by a simple lock nut, the arrangement having, as its outstanding advantage, that it considerably simplifies the adjustment of the tappet clearances.

The practice so frequently adopted with racing and sports cars, of affording each exhaust outlet its own separate pipe, is not followed in this chassis. Instead, the four pipes all discharge almost immediately into a large expansion box. It is claimed that this is better, and helps to reduce the back pressure within the cylinders. Another feature which we found of interest, was in connection with the arrangements for lubricating the engine. There is no pump of any sort fitted for circulating the oil. Instead, the flywheel is made to do that duty. As it rotates in its housing, it carries round with it some of the oil which is in the lower portion of the case, this oil is subsequently flung off, and is caught by buckets or troughs which are located in the inside of the housing. From there it runs along suitable

channels to the various points in the engine case and in the gearbox, where its presence is required. The electrical equipment includes separate dynamo and starter motor. The former is gear driven, and bolted to the timing case, the starter motor housing is bolted to the clutch housing. Provision is made for adjustment

We were given the opportunity to examine some of the detail parts of the engine, and can testify to the robust nature of the construction of the power unit as a whole. The connecting rod big ends were exceptionally large for the size of the engine, and the need for ample dimensions in such things as the cam and countershafts, and the timing gears, has evidently not been overlooked. The oil filler is made to do the double duty of serving as oil gauge and dipper. As a minor criticism we should mention that, according to our ideas of things, the filler could with advantage be made with a bigger mouth. Behind the engine—and the oil pumping flywheel— comes the clutch, which is of the disc type, running in oil, and the gearbox, which provides three speeds forward and one in reverse. It is centrally controlled. Behind that again comes a Hardy type universal joint of special design, with a centreing spigot which prevents lateral

movement of one half of the joint with regard to the other, without interfering in any way with its performance as a universal joint.

The rear axle is of the bevel type, with spiral gears, but embodies no differential gear. A good point is the provision for most accurate adjustment of the mesh of these gears, while the whole of the internal mechanism of the axle is accessible after the removal of a cover at the rear of the axle case.

All four brakes are operated together either by the hand lever or the pedal, as may be required. Each pair is compensated and a simple form of adjustment embodying easily accessible wing nuts is incorporated. The operation of the front wheel brakes is ingenious. The operating medium is a plunger, which is actually located within the centre of the steering pivot. As our illustration shows, this plunger is lifted from the bottom by a lever which is controlled by the brake operating gear. On the top end rests the lever which is secured to the expander spindle of the brake proper. The actual contact, between the lever and the top of the plunger, is made by a screw, by which adjustment can be effected.

Reference has been made to the efficiency of the springing, and the capacity which the grand Sports Amilcar has for holding the road, a capacity which mainly arises from suitability of suspension. It is therefore of corresponding increased interest to examine the means which are provided whereby this excellence of suspension are obtained. The front springs are semi-elliptic, and the rear springs are quarter-elliptic. To the front springs are fitted half Hartford shock absorbers, and to the rear, which are supported at their butt ends, on a substantial tubular cross member, full Hartfords are fitted. There is an unusual feature about the design of the frame. Instead of bringing the main side members right back, parallel to one another, they are swept

round to conform to the shape of the rear of the sports type body. This may seem a small point, but the arrangement has at least this one good point, it improves the appearance of the back of the car considerably. It is this insweep of the frame which makes it necessary to utilise a tubular cross member for the attachment of the butt ends of the set quarter-elliptic rear springs as is noted above

In the matter of small details, by which, often enough, a car will stand or fall, in the estimation of its purchaser, the makers of the Amilcar have nothing to fear. No split pins are used anywhere on the chassis except on the rear axle. Instead, small ” keeper ” washers, which turn down over the edge of the nut when it is finally screwed home, are utilised. One advantage of these washers is that they allow of fine adjustment of the parts wherever that is needed as, for instance, in the attachment of the caps to the big ends of the connecting rods.

The facia board equipment is very complete, including revolution counter as well as speedometer. The former is driven from a coupling on the timing case, while the latter derives its motion from the propeller shaft. It is surely an error, however, to supply instruments of this type to the English market figured in Kilometres. Presumably this is a matter which will be rectified shortly.

Rudge-Whitworth detachable wire wheels are fitted, the spare being conveniently located just forward of the driver on the off side. All points requiring the application of grease are equipped for the use of a Tecalemit grease gun—a good point this. The wiring is neat, two junction boxes being fitted in very accessible positions.

The Grand Sports Model is sold with a guarantee that it will do 75 m.p.h., and that its acceleration is such that a speed of 6o miles per hour can be reached in 300 yards. This and other. models of the Amilcar can all be obtained from the Sole Concessionnaires, Vernon Balls, of 25, High Street, Fulham, London, S.W.