THE SPEED SIX SUNBEAM
A COMFORTABLE, WELL APPOINTED TOURING SALOON, CAPABLE OF 80 M.P.H.
THE last sports car produced by the Sunbeam Motor Car Company was the Three Litre, a car capable of a very high performance if intelligently driven, but requiring a certain amount of skill to get the best results. The name Speed Model, which has been given to the present sporting model in the Sunbeam range, was doubtless intended to distinguish it from the rougher and less refined fast car of the past. The Speed Model then has a fine performance on the road, good maximum speed achieved with a silence which makes it ideal for Carrying closed coachwork and an outstanding top gear performance for a fast car. It suggests itself as being particularly suitable for a business man whose engagements compel him to cover long distances on the road and who wishes to reach his destination with the minimum of effort, but who is yet sensible of the pleasure of driving a thoroughbred car.
On taking the wheel one was impressed by the smooth engine and clutch, the good driving position, and the placing of the steering wheel, which comes exactly where It is wanted. The Sunbeam is a large car by present day standards, but the steering is light and easy and the flexible engine allows the car to trickle through traffic, and accelerate smartly without recourse to the gear-lever even from walking pace. The carburetter was excellent when the correct running temperature was reached. This does not take long, as the radiator is fitted with thermostatically Controlled shutters. The tun down to Brooklands track was soon made, and the usual tests were carried out. The concrete is not at its smoothest after a season of racing, but no discomfort was felt when lapping at full ‘speed. Repair. were going on near the fork, so most of the laps were made cutting up the Finishing Straight, and this gave a chance of trying the car on the corner used in the early Double Twelve races. We did not 30 80 70 40 ? So t 30 2.4 2o o 5 10 /5 20’es 3o 35 40 45 Se corvb S
take it quite as fast as Marinoni used to do on the Alfa, but fast enough to demonstrate the good road holding of the Sunbeam.
When using the outer circuit, 40 m.p.h. was the limit past the Fork, but in spite of this the car reached its maximum before the measured half-mile on the Railway Straight, and was timed to do 80.2 m.p.h. The speedometer readings were found to be considerably fast at the top end of the range.
The brakes were adequate, and always pulled the car up straight, however hard they were applied, but required a good deal of effort to get the full retarding effect. From 40 m.p.h. the car pulled up in 69 feet.
N() attempt was made to reach the maximum speed in the gears, as this was not called for with the flexible engine, but 37 m.p.h. on second and 55 on third were comfortably attained at 4,200 r.p.m., 80 m.p.h. on top corresponding to 4,150 r.p.m. A rev.-counter is not fitted as standard. The gear-change was straightforward and presented no difficulty. Straight pinions are used throughout, but the gear-box is well made, and after 20,000 miles was as quiet as many a box with constant-mesh ” silent ” ratios.
The gear-lever was rather far forward, and one’s coat-sleeve sometimes caught on the quick-lift window lifter. A longer lever can be fitted, and would overcome both these difficulties. The road test was carried out under varied conditions, all of which showed up the car’s ease of handling. Running fast along winding secondary roads, the accurate and fairly high-geared steering made it easy to hold an accurate course a foot from the edge of the road, while a good caster-action “centralised the control ” after sharp corners. The engine
was flexible enough to deal with all normal hills, with third gear as an alternative where a sharp rise was met with. Second was rarely used. On fast main roads the combination of a good power-weight ratio and a fairly low top gear encouraged fast motoring with a minimum of effort. The best cruising speed was around 65 m.p.h. and main-road hills were taken without any
drop in speed. A steady 55 could be maintained up the three mile climb up the Devil’s Punch Bowl, ending at Hindhead, without a suggestion that third gear was needed. 80 m.p.h. can be attained and passed on fast main roads such as that from Winchester to Basingstoke, and an average of 50 m.p.h. may be held without annoyance to driver or other road-users. The engine and exhaust note was subdued throughout the range, except for a certain roar slowing down from 80 to 75. A period, apparently in the transmission, could be felt, again when decelerating, from 55 to 50, but was so slight that it would probably pass unnoticed by the majority of drivers. The suspension was equally at home with all types of road surface, though for really fast cornering on acute bends, the shockabsorber setting was hardly stiff enough. This is of course a matter of personal
choice, and we did not feel justified in upsetting the satisfactory compromise which had been achieved by altering the shock absorbers to a racing setting for the duration of our test.
The Sunbeam can travel fast by night as well as by day. Powerful Lucas head lamps are fitted, with dipping beams, and are controlled by a switch in the centre of the steering wheel.
The engine is a straightforward six cylinder unit of clean design, rubber mounted at four points. Push-rod operated overhead valves are used, and the clearances are adjusted with the usual ball-headed screws in the rockers. Waterpump and dynamo are driven in tandem on the near side of the engine, and the distributor is mounted vertically. The oil filler is a large cap on the top of the valve-rocker cover, and there is an oillevel tap to show when the sump is full. The Zenith downdraught carburetter is accessible on the off-side. and is supplied by an A.C, pump from the 14 gallon rear rank. The pistons have alloy heads and steel skirts, and the
crankshaft is carried in four bearings and has a damper at the front end.
The dry-plate clutch and the gear-box are normal in type, with a right-hand change. The propellor shaft is enclosed in a torque tube, and conveys the drive to a spiral-bevel back-axle. Half-elliptic springs are used all round, damped by hydraulic shock-absorbers. The brakes are hydraulically operated, and the chassis is braced by a cruciform member. Chassis lubrication is effected from grouped oil nipples with one set on each steering pivot and the main group under the bonnet. The body of the Speed Model, which is made at the works at Wolverhampton, has handsome and distinguished lines, and an individuality which Sunbeam cars have always retained. It is a four-door saloon built under Silent Travel patents, and
since no centre pillar is used, getting in and out is particularly easy. Fine quality leather is used for covering the
seats, with latex rubber upholstery. The great advantage of this material is that there is no swaying when the car is taken fast round a corner, such as is sometimes felt with aircushions. The front seats have high backs which support the shoulders, and the sliding mechanism is readily released by accessible levers. The back seats are equally good, and have ample leg-room without recourse to deep foot wells.
Louvres are fitted at the top of each window, and by slightly lowering all four the interior is kept airy without draughts.
At the back of the body is a trunk which holds two suitcases and above them is a tray for the tools. The petrol filler cap projects from the back panel in an accessible position.
The Speed Model is a wellfound car typical of the products of the Sunbeam factory. It is built to give years of hard service with the minimum of attention. It costs complete £825. and the address of the makers is the Sunbeam Motor Car Company, Moorfield Works, Wolverhampton.
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