The Right Formula - 9 cwt. and 40 b.h.p.!

Impressive Prototype of New Cooper Sports Two-seater and — Some Notes on the Racing Coopers

“Motor Sport” has been preaching for some time the desirability of developing small or medium-sized sports cars in keeping with present-day austerity, i.e., cars giving a reasonable fuel consumption and entailing moderate maintenance charges while offering a genuine high performance. We have repeatedly suggested that if a good proprietary engine unit were installed in a really lightweight car these ideals could be attained simply and effectively. The use of a proprietary engine is suggested in order to offer the potential customer a known factor of reliability and established servicing charges, and also because the adoption (or adaptation) of such an engine simplifies production and so should materially reduce the purchase price of the car.

We have dealt with such cars as they have come to our notice, and none is more interesting than the prototype of the Cisitalia-like Cooper sports two-seater which we inspected at Surbiton last month. The recipe, briefly, is the chassis of the famous Cooper 500 (or 1,000) racing car and a moderately-“hotted” Vauxhall Twelve engine, which, converted into round figures, means a dry weight for the complete car, road-equipped, of approximately 9 cwt., and a power output in the region of 40 b.h.p.

The narrow channel-section chassis, with independent suspension front and back by fabricated wishbones and transverse leaf springs, is retained, but the length of the rear spring and wishbones is slightly increased to obviate all but half-an-inch of the crab-track of the racing car. Into the front, not rear, of this chassis has been installed the 1.4-litre Vauxhall Twelve engine, now with two S.U. carburetters and a four-branch exhaust system. The Vauxhall gearbox, controlled by a pleasantly-acting central gear-lever, is retained; also the normal propeller-shaft, while the Vauxhall rear-axle banjo is built neatly into the fabricated chassis member which usually accommodates the sprocket for the chain final-drive of the racing car. The i.r.s., incorporating universally-jointed driveshafts, is thus retained.

On to this chassis has been built a modern aerodynamically-clean two-seater body of 18-gauge light-alloy panels on a welded strip-steel framework, with a surprisingly roomy and comfortable cockpit, an aircraft-type drop-flap on each side assisting driver and passenger to enter and leave the car. A locker in.the rounded tail accommodates a 7-gallon fuel tank, the spare wheel, and the hood when furled, a fabric strip-cover closing the aperture. The prototype is professionally finished in blue, with the perhaps startling choice of red upholstery, and has a fold-flat screen, close-up wings, those at the front turning with the wheels, and headlamps set low down behind the nose-grille. The Vauxhall gear-lever is suitably cranked so as to be conveniently located, and a Ford “umbrella-handle” brake-lever, placed beside it, is cable-linked to the brakes.

The wheelbase of this sports Cooper is 7 ft. 1 in. and one’s first impression is that the car is remarkably small, an impression emphasised by the very low build (the top of the scuttle is only 2 ft. 7 1/2 in. from the ground) and the 15-in. tyres. (Actually the Cisitalia has a wheelbase of only 6 ft. 6f in., and the same size tyres.) The driver “wears,” rather than sits in, the car and visibility is truly excellent. The seating and driving position are notably comfortable, and the steering wheel, small and at present rather thick-rimmed, is pleasantly reminiscent of F.I.A.T. or Lancia. The scuttle has two wind-deflecting humps and the facia contents itself with four dials, unconnected or yet to be fitted when we examined the car.

A short drive showed the sports Cooper to be indeed an acceptable vehicle. It accelerated well, the engine revving in a manner that made downward changes, even on the three-speed gearbox, a slick business. The whole car felt taut, and it could be swerved from side to side with no loss of control. The Lockheed 2LS brakes, stamped on hard, were incredibly powerful, suggesting the dropping of a gigantic anchor; the steering was firm and accurate, and how anyone could ever have an accident in a car so responsive, so stable, and from which it is so easy to see, would be difficult to explain.

One of our contemporaries has described the suspension as deflecting excessively, while another states that the rear springing is a trifle harsh. We hesitate to disagree with such authorities, but to us the action seemed just right, for although there was some up-and-down motion over rough side roads, the comfortable upholstery absorbed all shock, and the little car rode on an absolutely level keel, with no pitching, so that the harshness over which vintage sports car folk enthuse certainly isn’t evident, while how a car that can be taken so fast through S-bends and be swung from kerb to kerb at speed without rolling can be said to have excessive suspension deflection we do not pretend to know. Praise must be bestowed on the Newton struts, but it has to be admitted that the rear spring had “settled” and may require stiffening up on production cars.

So far as performance is concerned, the engine is unobtrusive and acceleration therefore deceptive, but peak in the indirect gears was soon reached. Maximum speed on the present axle ratio of 4 to 1 is said to be approximately 84 m.p.h., but a 3.5-to-1 final drive is to be tried, when an even higher maximum, with a fuel consumption in the region of 30 m.p.g., even when driving hard, should be realised. The Cooper certainly has plenty of urge, it being possible to take corners or roundabouts in a power-slide with the tail floating outwards. It would make an admirable “racing-trainer” and an enterprising driver of a Cooper 500 or Cooper 1,000 could not do better than use a sports Cooper for his or her ordinary motoring, in order to become thoroughly accustomed to the marque’s handling characteristics.

It is only fair to say that the car described is a one-off prototype and that certain modifications will doubtless be made before production commences. Other engines may be tried, although, as Cooper’s Garage are Vauxhall agents and John Cooper’s father drives a new Vauxhall “Velox,” we may expect a Vauxhall unit to be strongly favoured. The petrol tank will be placed behind instead of in front of the back axle to provide a little luggage-space in the tail, and an even lower bonnet-line may be introduced — as it is, the valve cover is only about an inch below the panel. The price has yet to be settled, and an announcement will be keenly awaited, for there must be a big potential market for an up-to-the-minute 80 to 90-m.p.h. car using a reliable proprietary engine and other components, and which is economical even when optimum performance is used continually.

It is not possible to be blasé on a visit to Cooper’s Garage! For here British racing cars, not unjustly referred to as “miniature Auto-Unions,” are in brisk production. It all came about when John Cooper expressed a desire to compete in 500 Club events. His father, who used to prepare Kaye Don’s cars, including the notorious Wolseley “Viper,” produced the first Cooper, today the most successful of all the “500s.” John pressed him to go into production, so his father agreed to build a batch of twelve, using J.A.P. engines. That was about a twelve-month ago last January, and now the third dozen-batch of Coopers is well towards completion, and they are being shipped all over the world. Last year 24 cars were produced, into three of which V-twin 1,000-c.c. engines were installed, and this year ten owners already propose to fit such engines into their cars. The V-twin engine necessitates a slightly longer chassis and wider front wishbones are used. So far, no one is sure which will prove the better engine, the J.A.P. or the Vincent-H.R.D. At the time of our visit a Cooper with one of the former engines was on view in New York, while, as if to emphasise the world-demand for these little cars, in the showroom at Surbiton was a Cooper 500 destined for Sweden, which came within the customer’s stipulated weight-maximum of 500 lb. Incidentally, the idea of installing a V-twin engine came to the Coopers towards the end of 1947, and Rhiando provided John with a Speedway J.A.P. out of one of his Skirrows for the experiment, which, as we now know, proved highly successful. This season Stirling Moss, George Abecassis, John Appleton, George Hartwell, Leitch, Watkins, Baring, Andrews, Prosser, Pathey, Logan, Rhiando, John Cooper and, brave girl, Sylvia Bloomer, intend to race Cooper 1,000s.

The major parts of the Cooper chassis are of fabricated construction, shaped and welded-up in simple jigs, but so well finished Its to suggest machining from the solid. The bodies are made and painted at Surbiton. Interesting developments concern a neat Z.F. differential unit incorporated in the final drive sprocket, new magnesium-alloy wheels which are even lighter than the original aluminium alloy wheels, and the new combined fuel and oil tank above the engine. An 8 1/2 to 9-gallon long-range tank can be accommodated under the scuttle, and, if required, another can be fitted beneath the seat. Cooper has discovered that getting rid of the hot air is nearly as important as leading in cool air; air enters through scoops on the bonnet and under the seat and leaves via louvres and the open-ended tail. A minor modification relates to the angle of the seat-back, which now gives more room in the cockpit. These Coopers appeal as beautiful little racing cars which look essentially right and well finished — and which have certainly proved themselves in Competition.

Information about these 500-c.c. and 1,000-c.c. racing jobs and the new sports Cooper can be obtained from Cooper’s Garage, 243, Ewell Road, Surbiton, Surrey (Elmbridge 3346). — W. B.