GROUND CLERANCE-AND HOW!

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GROUND CLEARANCE AND HOW! DETAILS OF HEALEY’S INVICTA IN MONTE CARLO TRIM

FEW English competitors have had more experience of the Monte Carlo Rally than D. M. Healey, his finest performance of course being that of gaining the premier award in 1931, when he drove his Invicta from Stavanger, and the alterations which he has made for this year’s Rally are all of a very practical nature. The same car has travelled over 50,000 miles in all sorts of guises, from the stripped state in which it won its class in the Brighton Speed Trials last autumn

to the servo-clutch and slow-running equipment which it carried when competing in the Torquay Rally in March, 1932.

The car is a standard Invicta production, but the engine has a compression ratio slightly higher than normal and a duraluntin valve cover and sump. The mudguards are also of very light construction.

The most noticeable feature of the car as equipped for the ” Range ” this year is the size of the wheels and tyres. 23 inch wheels carry Fort Dunlop tyres of 7i inch section, the diameter of the tyre being therefore about 38 inches. This is the largest size of private car tyre made, …and gives the Invicta a ground clearance of some 18 inches. The photographs were taken at ground level in order to show this, but even from a normal standing position the car looks rather peculiar, the thin mtidguards exaggerating the .size of the wheels. The track rod is carried behind the front axle, and there is nothing underneath the car which can get caught up when it encounters heavy going. A Burgess silencer is fitted on the off side of the car, and though small seems very effective. Behind this a T Pipe allows exhaust gases to pass to the foot-warmer, and the main pipe terminates in a flexible tube and a fish-tail. To maintain the average speed in the night sections of the run good lamps are essential, for the car may easily be doing 70 m.p.h. in order to make up time. Unexpected corners are especially treacherous, for on Continental roads these are often covered with a sheet of ice. The Rotax lamps which were part of the car’s original equipment will probably be used and for dipping purposes one or more of the new Bosch fog lamps with divided mirrors and corrugated lenses. ‘These lamps throw a band of light about

a yard deep all round the front of the car, and in fog should be free from the dazzling reflection of stray upward beams. Inside the car alterations have been made to allow every inch of space to be used. The dashboard has been moved further under the scuttle, a small steering wheel has been fitted, and the gear-lever and its gate have been transferred to the driver’s left hand, all these changes being made to make it easy for a heavily clothed driver or passenger to get in or out. A Thermo-Rad exhaust heater is fitted into one of the wells on the back of the car, and the rear passenger should be able to lie more or less at full length along the rear seat. Unfortunately in the Rally the back of the car is liable to get full up with chains and such like articles, so the person who occupies the back seat will probably find a sheet of Sorbo very welcome. The chains inddently are the Dunlop rubber stud pattern, which strap round the wheels

at intervals. The hood has been raised at the back by fitting longer hood-sticks, and should allow plenty of air and headroom. Small alterations such as this make all the difference in riding comfort, especiall-y ,ts the hood will probably be left up for the whole of the five-day journey south.

With the floorboards out, the car rather suggests a dope-smuggling outfit, tin trays for spares and small articles being carried underneath, and a pair of particularly fine specimens are carried each side of the propellor shaft under the back seats. rwo small twelve-volt batteries in preference to two large six-volt ones are used, so that the car can still be started even though a cell should fail.

Luggage is carried in three minute suit-cases in a box at the rear of the car.

The car’s behaviour on rough ground was amazing. It was driven back and forward in all directions on a rubbish dump and nothing short of running the near-side wheels along the top and the off-side ones on level ground could bring the underside of the car in contact with terra firma. The grip of the large section tyres was such that no chains should be required, but these are being carried in case the spaces between the blocks of the tread get clogged on a thawing road. Steel skids are being prepared to fit under the front wheels in case of very heavy Snow.

T he engine develops so much power that with ordinary tyres the rear wheels spin. Healey wondered at one time whether twin rear. wheels, as used on the Terror, would not be useful in the acceleration test, but will probably use the large tyres with. which the car is at present fitted. Their mass and the area of the tread will prevent them from spinning, but only accurate timing will reveal whether the extra grip will compensate for the additional weight which has to be got off the mark. In 1931, it will be remembered, Healey was successful in winning the Rally from Stavanger, in spite of the ice-bound roads and the extremely difficult Tronaasen Pass. This year the regulations have been stiffened up so that the 25 m.p.h. has to be averaged between each check, so that no amount of fast driving on the southern portion of the route will compensate for lost time in the northern sections. In Healey’s opinion this puts Stavanger out

of court, and he sat up late on the last night on which entries could be accepted wondering whether to go from Athens or Tallinn. The difficulties to be encountered in the Balkans, no bridges, no sign-posts, and no road in case of a thaw setting in, decided him in favour of the latter. The journey from Tallinn is itself not too simple. The frozen ruts of the Baltic roads play havoc with the tyres, wearing away the side walls, and also causing tremendous strain on the wheels and steering gear when one tries to turn out of them. On a low car the sump and the petrol tank are liable to get carried away, but the unusual ground clearance should [Continued on page 156 get over this difficulty. In Poland the pot-holes are large enough, if not to bury the proverbial horse in, at any rate for a good sized dog, and here one hopes that

the 38 inch tyres will have a cushioning effect. Three people are travelling in the car, Donald 1-fealey, F. M. Montgomery, who

drove an M.G. from John o’ Groats in 1931, and a member of MOTOR SPORT staff. They are crossing to Antwerp and going North by car over the Rally route.

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