THE ALVIS “SPEED TWENTY” FOR 1933
NE of the most successful sports cars of 1932 was undoubtedly the Alvis “Speed Twenty.” Its performance was terrific, both in acceleration and in maximum speed, and the open sports model could be purchased for £695 ! No wonder the car was popular 1
Many new models are altered after a year’s use in private owners’ hands, but so much forethought had been expended on the design of the “Speed Twenty” that the car remains absolutelyunchanged for 1933. Here are a few details of the specification of the car. The engine has six cylinders of 73 x 100 mm., giving a cubic capacity of 2,511 c.c. The head is detachable, and the water spaces are particularly generous, in order to provide really effective cooling. An interesting point is that the gasket is not used to make a water-joint, for there are separate passages made between the cylinder block
and the head. The four-bearing crankshaft is heat-treated and balanced, and a vibration damper ensures complete smoothness throughout its range of revolutions (it can turn over at 4,500 r.p.m.) . The pistons are of special alloy, and the con-rods have bearing-surfaces die-cast into position. Situated at the rear of the engine, the camshaft and auxiliary drives are operated by Duplex chain, and lubrication is by pressure to crankshaft main and big end bearings, and to the valve rockers and push rod ends. Petrol is drawn from a 14i gallon rear tank by an A.C. mechanical pump to three S.U. carburettors. Ignition is by B.T.H. polar inductor magneto as well as special coil for starting in case the magneto should • fail to function, which is unlikely. •
A single plate clutch and 4 speed gearbox transmit the drive to spiral bevel rear axle and thence to the road wheels.
14 inch brake drums, semi elliptic springs,. one shot chassis lubrication and a double dropped frame complete the specification of one of England’s outstanding sports. cars. The low chassis frame gives coachbuilders plenty of scope for bodies of beautiful lines. Vanden Plas (England) 1923, Ltd., have always been noted as. specialists in sports coachwork and their range of bodies on the “Speed Twenty” Alvis are well up to their usual standard. Their models are a very good looking open four-seater, a two-seater sports, and a saloon. Messrs. Thrupp & Maberley, Ltd., turn out a beautifully finished sports saloon, which is entirely in accordance with this firm’s reputation for luxurious. coachwork on expensive chassis. Finally, the Mayfair Carriage Co., Ltd., produce a very striking saloon with beautiful lines, and here again a very high degree of finish has been obtained,