Motoring Notes
The Sports Invicta
MOST readers of these articles will know that the new 41-litre Sports Invicta won the recent Monte Carlo Rally, gaining the first prize irrespective of class from an international field of some 149 cars of different makes ; won the braking and acceleration tests after the Rally ; won the Mont des Mules hill climb, beating its class record, as well as four cups.
I have tried one of these cars (the only one in England at present) which had only a few hundred miles to its credit. After it has been run in for a few thousand miles it will be bound to improve on what is already a surprisingly good performance.
Taking the top gear ratio of 3.6 to 1, and an engine still very stiff, I think the following results of a test speak for themselves : in top gear an acceleration of from 10 to 30 m.p.h. was obtainable in 81 seconds ; and an acceleration of from 10 to 60 m.p.h. in 201 seconds. In third gear, from a standing start to 60 m.p.h. took 151 seconds.
Though it is called the Sports Invicta, this does not mean that__ it requires a "sports" or racing enthusiast to drive it. Far from this being so, the car is light to handle, can be started in third gear and, with a particularly simple change up, will do all its work, both in traffic and-on the track, in top gear. It is therefore eminently suitable for a woman to drive and handle. That it is quite unnecessary to change down for hills, or even for taking adVantage of traffic openings which call for great acceleration, must be an attractive novelty to many drivers.
This Sports chassis differs from the standard only in the following points : (1) The price is 2750 ; (2) the gear and compression ratios are slightly higher ; (3) the chassis is or new design, being exceptionally low throughout and under- slung at the rear ; (4) the normal speed on top gear is from 8 m.p.h. to approximately 100 m.p.h.
Having dispelled the illusion that this is merely a racing and competition car for experts, it is only right to explain just what coachwork can, and cannot, be fitted to it. Briefly, for four-door bodies, with or without a partition, the standard chassis must be used. The Sports chassis is suitable for two-seaters ; for four-seaters which comply with the Brooklands and International. competition measurements, and for a two-door sportsman's coupe, that is, one with two large seats in front and two small ones behind. As regards appearance : a long low bonnet, a chassis which permits of a comfortable touring body which is only 3 ft. 4 in. from the ground at its highest point, and a coupe of under 5 ft. in height, leaves a coachbuilder no excuse for not producing a most attractive result. I am not going to say that the coachbuilder has an easy task ; he has not, but, with skill, the bodywork can give adequate room and comfort to the passengers and still not interfere with a very remarkable performance.
The engine, which has already proved its worth for two years on the standard chassis, is 29 h.p., with six cylinders of 88.5 by 120.6 bore and stroke. It has both magneto and coil ignitions, and develops some 110 h.p. It has a four- bearing crankshaft, overhead valves with double springs, operated by pushrods with a very simple adjustment.
The feed is by pressure from a 20-gallon tank at the rear to two S.U. carburettors. Each carburettor normally feeds three cylinders, but there is a balance pipe between the two inlets for synchronization. In addition there is also a two-gallon reserve tank under the bonnet for gravity feed, and incorporated with it is a reserve tank for oil.
A fan is fitted, but no radiator shutters. Finding the engine ran rather too cool for maximum efficiency, I removed the fan belt and achieved a running temperature of approximately 80 degrees Centigrade, which was satisfactory. The dynamo is driven by a chain with external adjustment ; to it is attached the coil, make and break, and distributor at the back end in a very accessible position. Six plugs are set in each side of the head ; the oil filler and dipper rod and magneto are on the off side of the engine. Marks steering is used. A starting carburettor with adjustment on the dash is, I am informed, entirely successful in starting from cold. The clutch is of the dry single plate type ;_ the withdrawal can be lubricated from the dash with ease.
The clutch and gearbox are in unit construction with the engine. The normal gear ratios are 3.6, 4.9, 7 and 10.4, but a top gear of 2.9 can be supplied if required; The wheel- base is 9 ft. 6 in. and the track 4 ft. 8 in. one gear change is normally right-handed, but, at a small extra charge, central gear change can be fitted. I was glad to find the positions of the gears were marked clearly on the gate.
• Semi-elliptic springs with Luvac hydraulic shock absorbers are fitted all round ; the six brakes are directly operated by strong rods, each with a large and accessible adjusting nut. The chassis lubrication is by pressure gun of the quick push-on type. The usual instruments are fitted with the exception of the clock, which is replaced by a revolution counter. All plated parts, including engine pipes, lamps, &c., are chromium plated. The exhaust is carried in two chromium plated external pipes to a box- under the engine, and theme to the rear.
I have nothing but praise for the performance of the car on ' the road. It has remarkable qualities for acceleration and hill- climbing ; in addition it is definitely a top-gear car throughout its range, and it gives a -feeling of complete security on the road whether it be wet or dry, and at any speed. This i3 due to the very low centre of gravity- and correct weighs distribution, and also to good springing and shock absorber, but even perhaps more to brakes which are the best of any I have yet tried.
The clutch is smooth in operation, and does not slip; but it is rather heavy. The gearbox is a pleasure to use. A very slight acquaintance enables one to make perfect!. silent changes up or down at speed, and the change up from third to .top is so quick that it is a gteat help to a reallY quick " get-away." The complete car is sold at £950.
In view of its inaugural successes in France, the SPo Invicta should have a big success here.
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