1934 RACING CARS
1934 RACING CARS 4.-THE M.G. MAGNETTE, K.3.
THE ban on road-racing in Great Britain has prevented the general public from taking the interest in motor-racing which is found in Continental countries, and it is not surprising that since the Sunbeam Motor Company ceased to participate in foreign events, no F,nglish racing car capable of taking part in Grand Prix events has been made in a 13ritish. factory. Happily during the last few years the amazing efficiency of the British 750 c.c. engine has been demonstrated by Austin and by M.G., and with the production by the latter company of the 1,250 c.c. M.G. Magna came a demand for a supercharged version which could be driven in the under 1,100 c.c. events associated with many of the Grand Prix races. The task of the designers was not simplified by the fact that the car must also comply with the international sports car regulations in order to be eligible for the Ulster T.T. race, the only road event held in the British Isles. In its supercharged form, reduced to 1,100 c.c., the small six-.cylinder engine developed surprising power, and at its first public appearance in the 1933 Monte Carlo Rally it was found that the Magnette, as the new car was christened, had been virtually re-designed and was given an engine, chassis Mid brakes much more substantial than had been the usual practise for1100 c.c. cars. In the hand
of C. R. Wright it won the Mont des Mules Hill Climb in a time only bettered by a Mercedes the previrns year. Development continued, the most notable alteration being the fitting • of a Wilson pre-selective gear box. At this time Lord Howe, who had never ceased to hope for a car of British manufacture which he could drive on the Continent, conceived the idea of running a teath of Magnettes in the Italian Mille .Miglia, after the Targa Florio the most strenuous road race in the world. The cars were completed just in time and were shipped
direct from Fowey to Genoa. The cars were soon at Brescia, the starting point of the race, and after a fortnight in which Lord Howe, Sir Henry Birkin and George Eyston, not forgetting their co-drivers Hamilton, Rubin and Lurani got the feeling of their new mounts, the day of the race arrived. Birkin, whose furious driving was a by-word even on the Continent, was allotted the task of breaking up the opposition Maseratis, and made the terrific average of 87 m.p.h. between Brescia and Bologna. He was forced to retire near Siena with a broken valve, but not before Taruffini on the fastest Maserati had been disposed of. Meanwhile Lord Howe and Eyston forged steadily ahead and after traversing the tortuous Futa and Raticosi Passes came to Rome. The roads north again from Rome were equally arduous, and the drivers’ task was made no easier by trouble with ignition and lighting systems. However the little cars were still going splendidly and after regaining Bologna the drivers felt the worst was past. Finally after eighteen hours on the road, the inhabitants of Brescia saw the
first of the competitors approaching and amid great excitement the cars was made out to be Eyston’s Magnette, followed a minute later by the one driven by Lord Howe. In its first appearance in a Continental road-race therefore the Magnette gained first and second places in its class, and also the team prize.
Magnettes were next seen in the International Race at Brooklands, the novelty introduced by the Junior Car Club in which the Double 12 course is used, with varying courses through sandbanks instead of a time handicap. Hall was second, Mrs. Wisdom third and Lord Howe fourth, so the M.G. Company must have been well satisfied with the result.
The combination of acceleration and speed made victory in the Isle of Man Round Town race seem equally certain but all the cars were eliminated by back axle trouble. This was remarkable, considering that they had withstood the stresses of much more arduous Mille Anglia course, but the cause was found to have been the increased power and the constant use of the differential on the right-handed course. As a consequence, later models were fitted with a four-star differential, thus overcoming a fault which only racing could reveal.
Magnettes continued their successes in British events, with a third place for Manby Colegrave in the Empire Trophy, Nuvolari’s victory in the R.A.C. Tourist Trophy, and E. R. Hall’s win in the 500 Miles Race at 106.53 m.p.h., apart from fine performances at Shelsley and Donington. Abroad Whitney Straight’s sensational race in the 1,100 c.c. class of the Coppa Acerb°, in which he beat Barbieri on a Maserati by 1/5 second is especially notable.
The six-cylinder engine has a bore of 57 mm. and a stroke of 71 ram., giving a capacity of 1,086 c.c. The cylinder head carries two vertical overhead valves per cylinder, each with three springs, and they are operated by fingers which pass under a single overhead camshaft.
Each combustion chamber has its own inlet and exhaust port and the 14 mm. plugs are screwed into the off-side of the head. The ribbed induction pipe receives its mixture from the blower at the front end, and has a central explosion valve, while six branch-pipes on the near-side lead into the exhaust manifold.
The cylinder head and the block are both made of high chromium cast iron, and the crankcase is integral with the block. The machined crankshaft is carried in four plain bearings. The alloy pistons have three rings, and steel connecting rods are used with cast-in plain big-ends. The overhead camshaft is driven by a vertical shaft through spiral bevel gears, and the dynamo is integral with the shaft. A water pump is driven by a cross-shaft in front of the engine, and the B.T.H. Polar Inductor magneto, which runs at 2/3 engine speed, is similarly operated on the off-side.
The lubricating oil passes through a Tecalemit filter, and the ribbed elektron sump holds 1 I gallons. The supply is maintained by a float feed from the dash tank which holds a further two gallons. The supercharger is lubricated by a branch pipe from the overhead camshaft.
The standard fuel is 25% Ethyl and 75°o benzol.
On last year’s models a Powerplus No. 9 supercharger, of the eccentric vane type. was used, carried in front of the radiator and driven by a shaft and reduction gear at 2 3 engine speed. This supercharger will be retained for track races during 1934, but for road work a Marshall 2 vane type will be used, running at engine speed, in order to prevent the oiling of plugs at low speeds.
The compression ratio will be about 5.75 : 1, while the blower pressure will be approximately 12 lbs. No definite horse-power figure is given by the makers, but it is over 100 b.h.p. at 16,300 r.p.m. A single S.U. carburetter is standard, though two have been used, and it will be fed by an S.T. petrol pump. The fuel
tubular steel members, with a pressing at the rear end and a K shaped strut in the centre of the chassis. Friction shock absorbers are used back and front, four of these, set transversely, being used for the back axle.
The brakes are 11 inches in diameter, with wide drums, but the unsprung weight has been reduced as much as possible by using elektron back plates, shoes and drums with cast iron liners. They are operated by special cased cables. Torque braces from the front axle king-pins to the chassis sides relieve the front springs of the braking torque.
Cam-type steering is used, and a divided track rod has been found to have advantages over the standard lay-out. During 1933 most of the cars were fitted with a substantial two-seater tour
tank holds 23 gallons. The induction pipe is without the special slow minting hub used on the M.G. Midget, but is fitted with a Kigass spray to assist starting.
No clutch is fitted to the Magnette, as the friction bands in the Wilson preselective gear-box also serve to take up the drive. The gears are selected by a short lever mounted on an extension of the gear-box and moving in a serrated quadrant, and other controls such as slowrunning adjustment and the ignition lever are also carried there. The gear required is of course engaged by the depression and release of the pedal which replaces the clutch pedal.
With the usual back axle ratio of 4.89 the combined reductions through the gearbox are 4.89, 7.65, 978 and 16.6 to 1.
The propellor shaft is of the Hardy Spicer type with all-metal universal joints. while the back axle is of three-quarter floating design with straight-bevel final drive. The chassis frame is upswept over the front axle and underslung at the rear. and the flat semi-elliptic springs which are bound with cord move in slides at the rear ends. The chassis is braced with
lug body with a spare wheel at the back. though Alanby-Colegrave and Whitney Straight changed over to streamlined bodies, with a useful improvement in speed. Details of the 1934 bodies have not been settled, but they will probably be light racing bodies similar to the one used by Nuvolari in Ulster, while a short tail may be added. The car with two seater body costs £795. The chassis weight is approximately 14/ cwt., and with last year’s two seater body totalled 171 cwt., but with the light body the weight can be reduced to about 151 cwt. The all-out speed varies of course with the axle-ratio, but an idea can be gained from R. T. Horton’s record lap of 115.55 m.p.h. in the British Empire Trophy with the normal road-racing body,
Lord Howe is again taking a team of cars to Italy for the Milk ‘Anglia. He proposes to drive the whole way single-handed. with Thomas, his racing mechanic, as passenger. E. R. Hall will be the second member of the team driving with Mrs. Hall while Penn Hughes and Twain will be co-drivers on the third car. Eyston has ordered a team of three cars and will have as his other drivers Penn
Hughes and Wal Handley, the well-known racing motor-cyclist. The Magic Magna, of which more anon, is also being prepared for him, with Denby as spare driver and tuner-in-chief.
Kaye Don has ordered three cars which %%ill be driven by himself, Norman Black, and Jack Field, the Southport driver.
Mere, Yallop, Manby Colegrave and Hall will all be using their last year’s cars, while Roy Eccles, Bartlett, C. E. C. Martin, and Ford and Balmer. will also have Magnettes for the coming season, and Eccles and Ford have already entered their cars for Le Mans.
Kohlrausch, the well-known German driver, has ordered a Midget and a Magnette and these white-painted English cars will be seen in about 25 events in Germany during the coming season. Fork, another German driver, has also decided to buy a Magnette. As has already been announced in MOTOR SPORT, Horton is fitting his Maguette with a single-seater body with normal transmission and with the driver sitting on the right side, an arrangement he used with success on his Midget during 1933. George Eyston is having a special car built with off-set engine and transmission on the lines of the Magic Midget, which will be known as the Magic Magna. R. R. Jackson has also succumbed to the ” Monoposto ” craze, and is putting a singleseater on his car, which is the original Maguette which won the Mont des Mules Hill Climb.. A fourth single seater is
being built by a private individual but is very ” hush hush” at present. The Magnettes have certainly made a excellent showing during the past season, and promise to enliven racing circles at home and abroad during 1934. The next
thing to hope is that Mr. Kimber and his helpers down at Abingdon will turn their attention to something round the three litre mark, with which Great Britain can be adequately represented in the unlimited category.