A NEW SUPERCHARGED SPORTS CAR

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ALL students of design and connoisseurs of the sports car world will welcome the appearance of the new car which has recently been put on the market by the Squire Manufacturing Company, Ltd., Remenha in Hill

Works, Henley-on-Thames. Mr. Squire, the designer, has had experience of many types of sports cars, large and small, and refusing to be bound down by considerations of price has evolved a motor car which should make a name for itself in acceleration, road holding, and the other qualities which an exacting owner expects to have.

The power-unit is a supercharged fourcylinder double overhead-camshaft engine with bore and stroke of 69 and 100 mm., giving a capacity of 1,496 c.c. The camshafts are driven by a chain of double-helical gears from the rear end of the crankshaft, and each runs in 3 needleroller bearings. The valves are set at 90 degrees to one another in hemispherical combustion chambers in a detachable head, and are operated by short tappets of square section which are fitted with rollers where they bear on the cams. Valve clearance is adjusted by changing the hardened thimbles on the end of the tappet rods, an operation which is only required every 10,000 miles ; a special tool allows the valve cotters to be removed and the springs changed without dismantling. A sturdy crankshaft with extended webs is carried in three white metal bearings, with a fourth between the camshaft pinion and the flywheel ; the big-ends are also plain. The Roots-type supercharger is driven by single-helical gears from the front end of the crankshaft, and draws its mixture from a large S.U. carburetter, fed by a double electric pump from the 13-gallon rear tank. The induction pipe, which is well-finned, slopes evenly back from the engine. draining away surplus petrol when the throttle is suddenly shut and thus giving good slow running and a pick-up free

from flat-spots. It has two substantial blow-off valves and a Ki-Gass spray for starting from cold. The distributor, which is driven from the rear end of one of the camshafts, is a special high-speed Lucas product, which

is tested up to 8,000 r.p.m., and the coil is the largest type made. 14 mm. K.L.G. plugs are used. The rev, counter drive is taken from the rear of the off-side camshaft. The ribbed sump holds two gallons, and is well baffled to prevent the possibility

surging away from the pump inlet, A large ribbed Tecalemit filter is mounted beneath the radiator, with a bye-pass in case the cleaning element

becomes choked, and after passing through this cleaner the oil is pumped in the usual way to the hollow crankshaft, the camshafts and other points which require it. Two gallons of oil are carried in an auxiliary tank on the dash, and this is fed into the crank-case through a float chamber, which maintains the correct level in the sump.

A striking V-fronted radiator with a neat filler-cap is used, and there are two centrifugal water pumps mounted on the camshafts which force the water to the bottom of the cylinder-block on each side, with one central return pipe from the centre of the cylinder-head. The pumps are made watertight by carbon glands which require no lubrication.

Starting and lighting is effected by a very large dynamo mounted between the front dumb-irons, and the tests have -.1lown that it gives a certain start even in the coldest weather. The two units of the twelve-volt lighting set are carried on either side of the propeller-shaft.

A four-speed E.N.V. self-changing gearbox is used and is coupled to the engine by a shaft with two fabric universal joints and the engine and gearbox are each mounted on silentbloc bushes at three points. The gears are selected by a rotatable knob control on the steering column, which pulls out against a spring when one wishes to engage reverse. For night driving a special lamp lights up the knob without dazzling the driver.

An open propeller shaft with two universal joints transmits the drive to a semi-floating back axle, with spiral bevel drive. The final ratio on the 2-seater is 3.8 to 1. The chassis is a stout and well-braced structure 6 inches deep in the centre and tapering each end. It is upswept over both the axles, and widens out behind the

rear engine mounting. Apart from the tie-rods at the extremities of the chassis, there is a double tubular bracing in front of the radiator, a strutted box member to carry the front of the engine, a tube which passes under the flywheel and finally an X member amidships combined with two cross-members. The steel dash also helps to brace the centre section. Mr. Squire has left nothing to chance !

The semi-elliptic springs are pivoted at their inner ends and work in trunnions at the outer ends. Houdaille hydraulic shock-absorbers are used all round with the forward ones mounted behind the axle, so that the swing of the arms coincides with that of the springs, and really efficient rebound leaves are used in front. In this way it has been possible to provide a rigid suspenoion which is not jerky at low speeds. The springs, their pivots, the steering connections and other chassis points are lubricated through pipes from a pendulum pump mounted in the dash tank. Like Caesar’s wife the brakes on a fast sports car must be above suspicion, and those on the Squire, which are of the Lockheed hydraulic type, certainly should deal with every emergency. The drums and back-plates are of light alloy, specially heat-treated to ” age” them. The beautifully-ribbed drums are shrunk over the steel brake liners, and are then immovably held by a series of set-screws, while the operating pipes are of a specially strong type developed for the Merades racing cars. The hand-brake operates cams in the back drums through compensated cables. A dashboard control takes up the slack in the hand-brake control, forces the back shoes apart, and

thus by bringing back the pedal to its original position acts as a main adjustment. When all this is used up, the brakes are adjusted by the usual setscrews on each drum.

Two other points worthy of mention are the petrol tank with its baffles strengthening it at the four points at which it is carried on silentbloc bushes, and the comprehensive silencing system consisting of a Brooklands silencer, a touring silencer, and a Brooklands fishtail.

In spite of the sturdy construction of the chassis the weight complete is only 15 cwt., so that with an engine which must develop about 100 h.p. the acceleration should be forinidable. Two models will be made, a short one for two-seater bodies which costs £950, and a long chassis which costs £975. The wheelbase is respectively 8 ft. Gin, and 10 ft. 3 in., and the track is in each case 4 ft. 8 in. We look forward to publishing a road-test at an early date.