A SUPERCHARGED 1500 CC.
A SUPERCHARGED 1500 CC. VALE SPECIAL FOR RACING AND ROAD WORK
AN ENTERPRISING DESIGN WHICH INCLUDES A BELT-DRIVEN SUPERCHARGER, INDEPENDENTLY STEERED FRONT WHEELS AND AN UNDERSLUNG CHASSIS.
ON first encountering the Vale Special two or three years ago we were much struck by the way it handled and the care with which it it was built. At that time it was powered by an 850 cc. unit, which naturally limited the speed and performance, but since that time it has been found possible to install either an 1,100 cc. or a Iflitre unit into the same chassis. One of the most interesting of the new cars is a supercharged model which has been completed to the order of Mr. I. F. Connell and which we saw in process of building in the workshops of the Vale Engineering Company. It is intended primarily for racing, and will be driven at Donington and Brooklands, but later on will be fitted with hood windscreen and lamps and used on the road.
The engine, which is a sturdy-looking four-cylinder specially built for the Vale Company by Coventry Climax, is the first part of the design to be considered. A four-cylinder unit with overhead inlet valves operated by push-rods and side by side exhausts, it has a bore and stroke of 69 and 100 mm. respectively, giving a capacity of 1,496 cc. The off-side of the engine is dominated by the Centric supercharger, which is driven by twin rubber belts from the front end of the crankshaft. The induction port is in the centre of the top surface of the cylinder-head and the blower is mounted opposite this and connected through a short pipe with a blow-off valve. This position called for an extended drive to the blower, which has been carried out
by means of a short shaft supported at its extremity with a ball race, carried in its turn by a conical housing bolted on to the blower itself. The small quantity of oil
required for lubricating this component is supplied from a one-gallon tank on the dash. The induction pipe is connected to the tank though a small-bore pipe, and the pressure built up there helps to force the oil to its destination. A Solex horizontal carburettor is connected to the lower side of the supercharger by means of a short induction pipe with a right-angle
bend, and is at once accessible and close to the accelerator pedal to which it is connected by short and simple linkage.
The camshaft and auxiliaries are driven by silent chain located at the front end of the engine. The dynamo and the Scintilla magneto are connected in tandem, and there is a. separate swinging adjustment for the latter to give fine variations of timing. The water pump is bolted to the front end of the cylinder block, and is driven by a rubber belt from the crankshaft, independently of course of the supercharger drives.
On the near side of the engine is seen a large Tecalemit oil filter, which cleans the oil as it is forced to the bearings from the 2-gallon sump. A funnel-shaped oil filler is brought up level with the top of the cylinder-head.
Turning to the internals, the crank-shaft is machined out of the solid, and fully balanced, and runs in three main bearings. Plain bearings are used for the crankshaft and big-ends, the connecting rods are of steel and the pistons, machined from solid forgings, Aerolites. The cylinder block is made of Chromidium.
The compression ratio is 7.5 to 1, and the blower gives a pressure of 71 lbs., giving an effective compression of about 10 to 1. The fuel is 50 per cent. benzol and 50 per cent. racing Shell, and the engine is said to develop 97 h.p. at 5,700 r.p.m., with a top limit of ” six-four” if the driver wants to use it. The transmission is quite orthodox, with a Borg and Beck clutch, an E.N.V. four-speed straight-pinion gear-box with
central gear-lever, open propeller shaft of large diameter with needle-roller universals and spiral bevel back axle. The final reduction is 3.8 to 1, giving overall ratios of 3.8, 5.2, 7 and 12 to 1. Lockheed hydraulic brakes are fitted with a special push-on racing hand brake lever. Friction shock-absorbers are used front and rear, with two pairs controlling the rear axle. The chassis is of channel-section steel with four cross-members and additional bracing strips at the rear. A tubular front axle is used and following the design of the previous Vale Special models is actually carried above the side members, which are thus underslung and carried at a low level without introducing any complication. The chassis also passes under the rear axle and special springs with semi-elliptic silent bloc bushes in front, and rollers at the rear are used for both axles. The steering lay-out differs
from any other car at present on the road in being made without a track rod, with each front wheel steered by a drop arm from a cross-shaft carried across the chassis. The steering box is made by Messrs. Cam Gears. We recall that a similar system of linkage was successfully employed two years ago on Sir Malcolm Campbell’s Blue Bird, and it should prove equally good on a road-racing car, where accurate steering is of the same importance. The rear end of the body is devoted to a 16-gallon fuel tank, with two large Ashby filler caps in which are screwed special release valves similar to those used on heating radiators. These release valves will only be required when the electric petrol pump is in use, the feed normally being by means of a handoperated pressure pump. Another product of the House of Ashby used on the new Vale, is the special spring-spoke steering wheel which has spokes and
rim made out of the light weight Hiduminium alloy.
This promising lit-litre is fitted with a rakish two-seater body of racing outline with staggered seats, enclosed rear springs, and an attractive louvred bonnet, which has been built by the Berkeley Coachwork Company. As has been said, the car is produced as a dualpurpose vehicle, and ‘will be fitted with lighting and starting equipment, light mudguards and other all-weather gear which will not detract from its appearance or speed. The car weighs complete 141 cwt. and costs £625, while a similar car without supercharger is available at £400. Fitted with a four-cylinder 1,100 cc. engine the price is the same, and the chassis may be specified either with the racing or the standard Vale coachwork. The address of the makers is the Vale Engineering Company, Warrington Gardens, Portsdown Road, W. 9.