THE FIRST TO WEAR THE GREEN
SOME HITHERTO UNPUBLISHED INFORMATION ABOUT THE 2-LITRE AND 4-LITRE SUNBEAM RACING-CARS tThe Sunbeam Motor Car Co. Ltd., of Wolverhampton, was the only British concern to take a really active part in racing long before the advent of the E.R.A., and every enthusiast is interested in the racing productions of this great firm. We are privileged to be allowed to publish some exclusive information relating to these cars from the pen of Mr. J. L. Wyer, who was at Sunbeam’s when the 2-litre and 4-litre cars were being raced. We, no less than our readers, owe him a deep debt of gratitude for putting such data at our disposal.—Ed.]
iiAXING been asked by the Editor to write a few notes for MOTOR SPORT on the Sunbeam racing-cars of the nineteen-twenties, I must admit to feeling something of an impostor, for it was not until the early part of l 927,_ when the best of the -racing days were over, that I joined the old Sunbeam Motor Car Company. However, I made it my business, during the six years I spent with Sunbeam, to collect every shred of information available about the racing-cars.
I think that when I first joined the company as a pupil apprentice I had some vague idea that Louis Coat alen would at once recognise in me the one man he had been waiting for, and that I should immediately be co-opted into the racing department. It was, in fact, this belief, born of a fierce interest in racing-ears dating from early preparatory school days, which led me to persuade my parents that the motor trade offered the only possible career. The Sunbeam Company, as the only concern of the time with a genuine racing tradition, was the obvious choice, but the first six months of my novitiate, spent in the foundry, did much to cool my youthful ardour. However, I importuned everybody from the works manager downwards, and my face at the doors of the experimental department, peering for a glimpse of the racing-cars, became such a familiar and irritating sight that it was probably decided I should waste less time if I were allowed to be there officially.
At that time there were five racing-cars still at Sunbeam’s, namely, one of the 5-litre Indianapolis six-cylinder cars, the three supercharged 2-litre Grand Prix cars, and the twelve-cylinder 4-litre. The second 9-litre car was being built, and was completed in the spring of 1927. The S.T.D. combine was still actively racing with the straight eight 1i-litre Talbots, but these cars were built and maintained in Paris, and we never saw them in Wolverhampton. The only car being raced from the Sunbeam Experimental Department was the Indianapolis 5-litre which was being driven at Brooklands by Kaye Don. As a result of his performances with this car, he was provided, for the 1927 Whit-Monday meeting, with one of the 2-litre cars. I was clown at the track that day, and to my huge disappointment the Gold Star Race, in which the 2-litre was to run, was cancelled owing to rain. The race was run on the following Wednesday, and Don won easily at 118 m.p.h., the fastest lap, as far as I can remember, being at about 127 m.p.h. In September of that year, Billy Perkins, the famous Sunbeam racing mechanic, had something of a field day at Shelsley Walsh, being given three ears to drive—the 4-litre, one of the 2-litres, and a standard 3-litre saloon for the formula class. This was one of the few occasions on which Perkins was given an opportunity to show what he could do, and he had the worst possible
luck. I have been to many Shelsleys since, but never remember heavier rain, and the racing Sunbeams were possibly the most unsuitable machines for the occasion. That was before the hill was surfaced, and according to Perkins’s own version, he lost at least 7 seconds with the 4-litre before he could even get it off the line. His best time, with the 2-litre car, was, I believe, about. 56 sees., and the 4-litre was a second or so slower.
In the following year Don was given the 4-litre car for the Gold Star, and won again, this time at 128 m.p.h. One of the 2-litres was sold to Jack Dunfee, another to W. B. Scott. I have omitted to mention that one of the 2-litre cars was driven at Shelsley in 1928 by Miss May Cunliffe, who took the Women’s record in 51.2 sees. Later she drove the same car at Southport where she crashed, her father, who Was riding with her, being killed. This car, which incidentally was the same one which Dario Resta had crashed at Brooklands in 1925, was brought back to the works and rebuilt, and was, I believe, the one eventually sold to W. B. Scott.
Don continued to drive the 4-litre car with some success, taking the Brooklands Outer Circuit Lap Record at 137.58 m.p.h., and then the world’s standing mile at just over 100 m.p.h. The two 4-litres and Don’s 2-litre were run in the B.R.D.C. 500 Mile Race as a team in 1929, but that was virtually the end of the racing activities of the Sunbeam Company. Financial difficulties had begun seriously to intervene, and the racing-cars were finally sold, the last of the 2-litres, I believe, to E. L. Bouts, and the two 4-litres to Sir Malcolm Campbell. Now for a few words about the ears
themselves. Unfortunately, my own experience was limited to the supercharged 2 and 4-litre cars, since, as mentioned above, only one of the Indianapolis cars remained when I joined the firm, and all the others were well before my time. The constructional details of the 2-litre engines are quite well known, and I will only recapitulate briefly. The cylinders were machined from the solid billet, and welded up in blocks of three, with thin sheet steel water jackets. Cam boxes were aluminium castings, and were bolted on to the cylinder blocks. Cam covers, crankcase, sump, and timing gear covers were, of course, all east in aluminium. Twin overhead cain slaut.I s operated the 45′ inclined 0.11. valves, which had triple valve springs. Lubrication was dry sump, and there was a 20-gallon oil tank stretching the full width of the chassis mule r the drive T’S seat. Originally one magneto was fitted transversely on the near side and driven from the timing gears, which were at the rear of the engine. In this position it was very close to the exhaust branch from No. 6 cylinder, and later two magnetos were fitted, driven from the near side camshaft, and projecting into the cockpit. Both were permanently running, although only one was in use at any One time. These engines were fitted with roller bearings throughout, and an interesting point was the use of split races of Italian bronze. The upper
race was held in position by a cap and could be assembkd in the same manner as a normal plain bearing. In spite of gloomy prophecies I never heard of a case of these bearings giving trouble. These cars were designed in Paris by Bertarione, but the designs were very largely redrawn, and all the detail draw ings prepared, in Wolverhampton. The man responsible for most of this work was George Ward, but in spite of the very large part he played in the successful design of the cars, he never saw one of them in action. When I first met Ward he hada never driven a car, and tt was not until years later that he bought
a secondhand Singer saloon, his first car. He was an extremely charming. fellow and allowed me to waste many hours of his lime while he answered my questions about the racing-cars. The 4-litre cars, were, of course, fundamentally similar, but we re not, as some people suppose, merely two of the 2-litre cylinder ass e mblies on a common crankcase. In point of fact, the 4-litre differed from the 2-litre in that the cylinders were welded up in blocks of two, instead of blocks of three. As originally designed by Bertarione, the 4-litre had one large supercharger, driven from the nose of the crankshaft, which served as the front engine bearer. This layout gave trouble during the successful world’s record attempt at Southport (when Segrave did 152.33 m.p.h. for the kilo.) and was subsequently medificd to allow for two smaller superchargers. Both fed into a common induction manifold of very simple design, which ran between the banks of cylinders and fed the ports through downward leads. This pipe was known in the works as the “sow pipe,” for obvious reasons. The medified layout was designed and developed entirely at Wolverhampton, by George Ward and Capt. J. S. Irving. Apart from the early supercharger difficulty these engines
were extremely reliable, and the retirements of these ears in long-distance events were caused by transmission or chassis weaknesses, and not by engine failures.
It has always been my opinion that these 4-litre engines represented the peak of Sunbeam racing development. The maximum output of about $00 b.h.p. at 5,000 r.p.m., representing 75 b.h.p. per litre, was certainly not high by Modern standards, but it must be reinembcred that compression ratio was only 5.9 to 1, and the supercharge pressure only about 8 lbs. per square inch. No attempt was made to develop the engine beyond this point, and there is no doubt in my mind that with suitable development and modern fuels the power output could easily be increased to 100 b.h.p. per litre with complete reliability. On E2 fuel the 4-litre engine developed about 305 b.h.p. at 5,000 r.p.m., and the curve was still , rising steeply. Power readings were never taken at a higher engine speed than 5,000 r.p.m., but when testing a new crankcase breather layout, the engine was run up to 5,500 r.p.m. on the bench, and during the standing Mile record attempt this engine speed was certainly attained, probably exceeded. The maximum b.M.e.p. was little higher than for the 2-litre, but it was attained at a very much lower speed and the b.m.e.p. curve was much flatter, giving the car a terrific performance throughout the range. Don’s figure of just over 100 m.p.h. for the standing mile record was not beaten until the advent of the German racing-cars in the middle nineteen-thirties.
Behind the engines the 2-litre and 4litre cars were very similar, and many parts of the transmission were identical. A Hele-Shaw clutch transmitted the power to the four-speed gearbox, a detail differ,ence being that on the 2-litre the :gear change was central, whereas on the 4-litre it was right hand with the lever passing through the side of the body. Brakes were operated by a mechanical servo of Hispann-Suiza. design at the back of the gearbox. A similar system was used on certain Sunbeam production models. The chassis side-members Were curved, in plan view, at the rear, to follow the profile of the streamlined tail, and as the radius was very large this caused some headaches for the designers in laying out the rear end of the chassis.
Both cars were very light, the 2-litre weighing under 14 cwt. and the 4-litre, in its original form, under 15 ewt. As rebuilt by Campbell these ears were much heavier, weighing about 17 cwt., and the performance suffered accordingly. Both ears were regularly tested on the roads round Wolverhampton, the most favoured venue being Crackleybank, on Watling Street, between Oitkengates and Cannock. Some very high speeds were attained. Both Billy Perkins and Vie Cozens frequently reached 130 m.p.h. with the 2-litre ears, and Perkins was said to have reached 143 m.p.h. with the 4-litre. On a shorter, downhill, and by no means straight piece of road near Himley, Perkins reached 117 m.p.h. with the 4-litre. The fuel used for all normal testing and for driving the ears up to
Brooklands before a meeting was petrol from the works pump, but for racing the fuel was normally 60/40 petrol-henzole. The cars were perfectly tractable on the road and could be driven at quite low speeds without fouling plugs. The 2-litre gave a more comfortable ride than the 4-litre, possibly on account of better weight distribution.
Before leaving the subject of-the rakingcars, I should like to endeavour to answer the vexed question of the fate of the 1923 Grand Prix cars, one of which won the French Grand Prix in Segrave’s hands at 75.3 m.p.h. Like most other enthusiasts I was puzzled by the fact that these famous cars never reappeared, and as soon as the opportunity arose I naturally satisfied my curiosity on this point. The plain and unromantic facts are that these cars were stripped down after the French Grand Prix, and wherever possible the components were used in the 1924 supercharged cars. The cylinder block assemblies, for example, were identical. The remaining parts were scrapped, and for many years one of the chassis frames, complete with most of the body, lay on the works dump at Sunbeam’s—a sad ending to what may have been the winning car. I remember having ideas about removing the remains, fitting some sort of engine, and turning it into a sprint machine, and actually gathered together a number of the other apprentices to share the financial burden, but for some reason the scheme fell through. I hope this will set at rest the minds of some of those enthusiasts who have written to the motoring Press on this subject during the last 10 or 15 years.
While not strictly within the scope of these notes, I think One of the most interesting features of being in a big works is the intimate glimpses one obtains of cars which never reach the public. There were plenty of these at Sunbeam’s, and I was never able to understand why development of one model would be cut short, while another, apparently far less promising, machine would be persevered with until it was placed on the market. In the former category was the 5-litre straight-tight. This was not the production tight-cylinder of 1927, of which Sixty-five were built (in 35 h.p. and 30 h.p. sports forms.), but a much later job designed in about 1930 by Attwood. An aluminium cylinder block was used, with wet liners, and it was generally quite an advanced design. It was fitted with a very good-looking fabric saloon body, similar in outline to the Gurney Nutting body on the modern Bentley, and as the car was low built the appearanc4 was most impressive. A feature of this car was that to obtain any sort of directional stability excessive caster angle had to be used, actually about 5′, and this resulted in very heavy steering. This could probably have been cured by better weight distribution. I forget the power output of this engine, but the only time I rode in the car it ran up very easily to 87 m.p.h., and would certainly have done over 90. Another very interesting job was a six-cylinder 3-litre engine designed at about the same period by Hugh Rose. This also had an aluminium cylinder
block with wet liners, and in other respects had a strongly Riley flavour, with two camshafts mounted high in the block operating through short push rods to 450 i nen feed valves in he misp he rical heads. The power output of this unit was disappointing, being just over 70 b.h.p. at 3,600 r.p.m., but this was almost certainly due very largely to poor manifolding. The manifold itself was a straight rake gallery cast into the head, and either one or two horizontal carburetters were fitted to choice, without much apparent effect. on the output. This unit MIS never installed in a chassis, but two engines were built, and reposed for a long time in the obsolete stores. They would have formed a promising basis for a sports-car. The supercharged 3-litre was not perhaps in the same category, since it was listed for a time 4s a production model, but actually only six were built, the mini MUM number prescribed by the regulations of the Irish Grand Prix, for which the car was built. Four of these ears were subsequently converted to standard form before being sold, including the first experimental car, which
was a Weymann saloon. engine was, of course, basically the normal, twin overhead camshaft 3-litrc, with a Cozette supercharger rather insecurely attached to the side of the crankcase. The blower was driven through a long shaft from the water pump, and in the words of George Ward, who designed it, it was “a bad botch.” The Cozette carburetter probably took the .W.orld’s record for inaccessibility, as it was fitted below the supercharger, and could only be reached through a hole in the undershield. Blower pressure was 5/0 lbs. per square inch. The power output was 140 b.h.p. at 3,800 r.p.m. compared with 90 b.h.p. from the normal 3-litre. The greatest difficulty we experienced with these cars was clutch slip, since the standard 3-litre clutch was used and it was just not equal to transmitting the increased power. This caused the car’s retirement in the Irish -Grand Prix in 1929 where Campb( hi drove it.
This engine was JIM d in I he normal 11 foot wheelbase 3-litre cia sis and I lw maximum speed was about 112 m.p.h.. although Perkins was said to have reached 110 m.p.h. (fowl’ Crackleyban k. The actual race car was subsequently sold to B. 0. Davies, who drove it in t he Irish Grand Prix the following year, but retired after six laps with a fractured supercharger easing. Davies also drove the car at Brooklands, where he lapped at 107 m..p.h.
The only remaining car Of this series was sold to Walter Hammond, who drove it for a time in supercharged form, but I did hear that this machine was ultimately converted to standard, and it seems doubtful if any of these engines are still in existence. Reading through these notes, it Seems that I have left out more than I have included. Although I made copious notes at the thne, most of them seem to have been lost during the intervening years, and I must ask critical readers to forgive any sins of omission. Should these lints come to the eyes of anyone
who was at Sunbeam’s during the same period, I hope they will overlook any inaccuracies. One final word. Talking the other day to Sammy North, of Zenith, I heard the first news I have had for many years of some of the old Sunbeam frater ; Billy Perkins, who has a workshop Wolverhampton; Fred Wilding, was manager of the experimental and Reg. Harold, who was foreI hope, when there is time, to contact with all these old and refresh my memory regard
the racing machines, which still such a strong fascination. [In company with Anthony Heal, has since visited Perkins, and we invited him to write some Sunbeam reminiscences for us, this visit.-Ed.]