A RACING CAR IN RETIREMENT SOME DETAILS OF THE 11/2 LITRE ALVIS WHICH WON THE 1923 200-MILE RACE
A RACING CAR IN RETIREMENT SOME DETAILS OF THE 11-LITRE ALVIS WHICH WON THE 1923 200-MILE RACE
THE 12/50 h.p. Alvis is known to be one of the better vintage motor cars and it is much in demand by enthusiasts in consequence. The original aluminium-bodied 12/50 was sold in 1925 with a guaranteed speed of 70 m.p.h. The engine is quite able to stand considerable hotting up, and in 1923 C. M. Harvey won the J.C.C. 200 Mile Race with a single-seater Alvis which was believed to be a fairly normal 12/50 developed for racing work. The Alvis averaged 93.29 m.p.h. for the 200 miles. Until recently, we had never been able to .ascertain how far this car departed from standard, but some interesting particulars, for which we are indebted to G. FennWiggin, who is now part-owner of the old 42ar with Swain, throw informative light on the Subjeet. They also indicate what might be done to ordinary 12/50$ to make them go even quicker than they do now, for, while it is normally unwise to base tuning recommendations for a type on experiments conducted on one engine only, this Alvis is rather an exception, being still active and reliable after sixteen years' running—indeed it finished third In the 4 lap unlimited handicap race at the Vintage S.C.C. Doning,ton meeting In July 1937. Incidentally, the Alvis now carries a sports two-seater body and not the high monoposto body used in the race. The standard 12/50 cylinder block is linered to a bore of 68 mm. while the stroke is 103 min. (1,496 c.c.). The crankshaft is standard in design, but carefully polished and balanced. 'The head. is the normal big-port 12/50 head, but with unmasked plug-holes and cleaned up and polished ports. The exhaust system is of three branch type, the off-takes going straight out through the bonnet sides. The brass inlet manifold has easy curves and is polished internally and is encircled by the central exhaust off-take. The Solex carburetter is similar to that fitted as standard, but the choke is very large and extends about 4 inch as the bottom of the air-intake is cut away ; a 35 jet is used. The COM prission-ratio is 9 to 1, but the car runs well on Discol or 50/50 petrol/benzole. The camshaft is special and the inlet valves are of exaggerated tulip foi mat ion, with standard exhaust valves. Ntw inlet valves, to the exact shape of the oliginals, were made up for the present owners by the Wolverhampton Valve Co. for 8/6 each. The connecting-rods appear to both pumps. The lower pump scavenges and the upper one feeds through the side of the sump as in ordinary 12/50 design, while the suction side is also led to the exterior of the stamp and thence to the 3 gallon exterior tank. The scavenge pump draws oil from what would be the oil-level float tunnel on the standard engine. The tunnel base has a plate
be standard ones machined to a thickness of * of an inth. and polished all over. However, the gudgeon-pin clamp has no slot, the bolt merely acting as a cotter. Alvis can supply rod.s. without the slotted clamp and charged FennWiggin for machining one down. The pistons have flat crowns, dropped at the sides for valve clearance. Dry sump lubrication is used, with the oil-pumps in the normal position, the bottom one being driven by a shaft which passes through the upper pump and which is slightly longer than standard to drive
and filter in place of the usual base and from this filter oil is led back to the tank. Castrol " R " lubricant is used and the pressure is 100 lb. per square inch.
The magneto is 'a Simms S.R.L. type with double contact breaker springs. Flywheel and clutch are completely non-standard, the clutch being of internal cone type with light alloy parts. • The E.N.V. gearbox is in unit with the engine and has a central lever and very close ratios. The E.N.V. rear axle has no differential and a final drive ratio of 3.8 to 1. The tyres are 19" x4.00."
THE M.C.C. EXETER TRIAL RESULTS
One hundred and thirty cars and six tricars started in the classic M.C.C. Trial, first big trial of 1939 and the first event under the comps.-barred ruling. One hundred and four Premiers, fourteen Silvers and four Bronze medals were won and there were nine retirements. Five cars finished without gaining an award. The makes which fell by the roadside were an Austin Seven, a Bentley, three M.G.s, a Morgan 4/4, two Singers, and a Wolseley. The Frazer-Nash-B.M.W. team took the Team Award, beating the lflitre M.G. team by .2 of a second. The two Allards, the works Big Seven Austin saloons, the Batten-Special, two old-school Bentleys, all nine B.IVI.W.s, both H.R.G.s, two Hillman Minxes, a 2-litre Lagonda, the L.M.B., all the Morgan 4/4s, two S.S.s, a Steyr, Talbot, two Trojans, a Wolseley and Woodall's Wolseley-Ford-Special deserve praise because they are either lone entries, or
mass entries of one marque, tO net Premiers. Ford, M.G., Riley and Singer also accounted for lots of Premiers. Of five Frazer-Nashes, three got Premiers and the others Bronze medals, E. G. Sm ith's Austin Seven three-wheeled Ulster got a Silver, Cope's auxiliaryengined B.S.A.. three-wheeler got a Premier, the two :Morgan throe-wheelers landed Silvers and Ginn's Menace (B.S.A. three-wheeler with driven rear wheel) failed to get an award.
"SEE HOW THEY FLY" AT SHELL ME X HOUSE
An exhibition a aviation, arranged by Shell-Mex and B.P. Ltd., was opened on January 4th by Lt.-Col. J. T. C. MooreBrabazon, M.C„ M.P., holder of the first pilot's licence in the United Kingdom. The exhibition will appeal to a variety of tastes ; if volt want to see how an CNhibition of photographs, models and diagrams should be laid out you will see it
here : if you are interested in air mail stamps here is a collection. lf you would like to sit in the cockpit of a modern machine and work the controls of a model aeroplane set before you it a wind tunnel you can do it here. You can see how an aerial survey is done, how a pilot is guided by wireless to earth in a fog. If you are interested in arclueology yOu will see ghosts of the past and outlines of forgotten ways and places revealed by aerial photography. You will see a model showing how a pilot flying due west and travelling at 500 miles an hour would keep pace with time. You will see the world air port of the future, and, perhaps most int crest Mg of all, reproductions Of a range of natural flying types and models of man's groping efforts to copy them, from the pterodactyl to the machine with which the Wright brothers heralded the dawn of modern aviation.
The exhibition is open from 10 a.m. to 7 p.m., Saturdays included. Admission is free.