TWO RACING CARS RE-BUILT
INTERESTING WORK CARRIED OUT ON M.G. AND AMILCAR
Progress moves swiftly in the racingcar world, and the most certain road to success is to buy the latest .a.ms.. mod, .1 soon as the new cars have proved themselves. On the other hand, given resources and technical knowledge it is often possible to renovate and re-desigu an older car bought at a moderate lure and to tune it to compete successfully with the latest products of the factory.
Last month we i messed a striking instance of this in t he shape of .1 special M.G. Midget which is being constructed for Mr. W. E. El umphries, a well-known track driver, who has scored several successes, at firooklands with Am i Icars and Other makes. Mr. Humphries believes in at to details, so as a preliminary move, the chassis, which belonged originally to a 1932 1.3 supercharged Midget, was stripped down to the last hi iii . The side-members were polished and chromium plated as a pn?t.,ction against rust and to make it easy to detect: ,c racks, or other faults while t he cross members were stove-en amelle,I. The chassis was then built up with scrupulous .c are’, each bolt being hand-made from 80-ton steel and fitting its particular hole. The .holes were hand-reamer, 1 and the heads of the bolts marked to ‘correspond to a numbered plan. With this eare in fitting and by the addition of a light cross-member in the centre of the chassis the owner expects to obtain greatly increased rigidity with minimum weight. The front axle is a special pattern fitted with cables to
Screntificlightening on :l/r. Zeri I dew’,
resist the braking torqu, while the brake drums have been lightened with large holes which are protected against the ingress of water by light at plates. The work on the chassis has taken -18 months to complete. After working for some time on the 1-.3 engine and designing a new crankshaft and other parts, it was decided to scrap in favour of the more robust three. bearing (2-type motor. Here again under care of NI ajor Oates; the crankshaft
was re-balanced and entirely new connect ing-rods, bearings pinions and
ot her parts installed. Copper-fil 1 f.’d valvt.’.ti are used, and t he cylinder head is lapped on to the block. which is re-built for this iii(ing season
The ignition is by means of a Scintilla Vertex magneto, and of the dynamo only the shell remains. A Murray Jamieson t n-rotor supo,rcharger is bolted direct on to the fron t end of the crankcase by tneans of a nose-piece, the front end of the blower being steadied by Silentbloc hushes on the dumb-iron tie-rod. Two S. U. carburetters are used. The car will be fitted with an off-set single-seater body running smoothly into a lengthy tail. The radiator will be a
separate entity with its own cowling and air-vents in front of the bonnet proper.
Mr. H uutphries will be running his car at Donington in April and at Brook1 tt.ds in the Empire Trophy and the holiday meetings. lie also considers that the car should be capable of attacking some of the 750 c.c. records. The other tar is one of the famous sixcylinder supercharged 1,100 c.c. Amil cars. It first saw the light of day in 1926, but with its two overhead camshafts • gear-driven from the rear of the engine, is more than up-to-date even to-day. A ft or a successful career at Brookl ands, it was put out of action
Wit Ii a con-rod through the crankcase. and was picked up by its pr sent owner, Mr. E. P. Zer6, of Z. N. Motors, for
£90. Mr. Zert’,. aS responsible for tuning the A milcar with which W idengren secured class records some years ago, Si:) presumably he knows just what 11K. car:-; can be made to do. The first part to be tackle.d was obviously the engine, and the crankcase was successfully welded and the damaged cylinder dealt with by inserting a liner. The main bearings a rid big rods have been lined with a special metal, lead with a little tin and impregnated with graphite, which had oved a real insurance against failure in those parts. The oil-tank, which formed
part of the dry-sump lubricating system is being transferred from the front dumbirons, where it was subject to air locks, to the back of the dash, and a special pressure filter has been designed to int, rpose between pump and bearings. Better combustion and freedom from oiling is obtained by enlarging the
masked holes leading from the combust ion chambers to the sparking plugs.
The head beds down on a special fivelayer copper-steel gasket.
The chassis has been extended rearwards below and behind the rear axle. The extensions are welded in . position with pieces of channel section over the joins. This extra length of chassis will make it possible to bring down the top of the petrol tank almost level with the tops of the wheels. Longer rear springs are now fitted, increasing the wheelbase to 7 ft. 8 in.
The chassis weight is by no means excessive, being 13 cwt. as against the 11 cwt. of the four-cylinder chassis in which the Frenchman, Scaron, used to house his six, but Mr. Zere is not satisfied with that. He has cut triangular sections out of the chassis behind the rear-spring mountings, drilled the rear cross-members, the engine mountings, and every other part which he considers a little overweight. With a blue-painted chassis and highly-polished metal parts, this little car was a real joy to the eye of the enthusiast, and if workmanship is any criterion, should acquit itself well when completed. Like the M.G., it will be fitted with an off-set single-seater body, but with a short road-racing tail. It was built primarily with the idea of competing at Donington and in some of the numerous Irish road events. Mr. Zere also plans to run it in outer-circuit races at Brooklands, and if it reaches the speed he
The Amilcar in process of reconstrudion. Some of the chassis lightening can be discerned under the back springs and in the/rear cross members. The finned component is the
special oil filter.
anticipates—unfortunately this cannot for the minute be disclosed—it should revise one’s idea of the performance of a ten-year-old 1,100 c.c. car.