Hydro-Pneumatic All-Independent Suspension, Hydraulic Clutch, Gearbox and Steering, and Inboard Disc Front Brakes Make the Long-Awaited Front-Drive Successor to the Famous Light Fifteen the Sensation of the Paris and London Motor Shows.
The new Citroën DS19 is more revolutionary today than the F.W.D. Twelve was in 1933. The rubber-mounted engine is a 75-b.h.p. version of the previous 56-b.h.p. Light Fifteen four-cylinder 1,911-c.c. wet-liner unit, with entirely new inclined (60-deg.) o.h.v. light-alloy head with special valve gear, and a Weber twin-choke carburetter. The shrouded fan has eight flexible nylon blades and the ignition system has twin coils and contact-breakers replacing a normal distributor, sparks, happening on exhaust as well as firing stroke. The single-plate clutch is automatically operated, both for gear-changing and in conjunction with engine speed, dispensing with a pedal, by the hydraulic system which is a feature of this remarkable car, its take-up being modulated in accordance with a normal get-away or a “racing” start.
Ahead of the engine is a four-speed-and-reverse gearbox, with synchromesh on all except bottom gear, driving the front wheels via a 3.4 to 1 spiral-bevel final-drive. Gear-changing is effected hydraulically, but is controlled by a tiny lever ahead of the steering wheel, working in as little gate on the dash. The gear-lever operates the starter (as on the Leyland Eight of 1920). A manually-operated valve enables a gear to be engaged, if desired, without the clutch disengaging, for safety when parking on hills, this same control frees the clutch for servicing operations.
Suspension is hydro-pneumatic front and back, with built-in dampers and anti-roll bars, pressure being supplied from a seven-cylinder pump belt-driven from the engine, a system giving an uncannily level ride, which was tested on the back of the Citroën. The brakes are hydraulic, those at the front, for the first time on a mass-produced car, being inboard air-cooled disc-brakes. Conventional 10-in. dia. drums are used at the back. These brakes, self-compensating for wear, are applied by a button on the floor possessing only a small travel, and distribution of front/back braking force is automatically compensated according to the load carried. Separate hydraulic reservoirs are used for front and back systems, fed by separate pipe-lines. A second, larger brake pedal applies the front brakes mechanically and can be locked-on for parking by an under-dash control, this pedal replacing the usual hand-lever. The rack-and-pinion steering is hydraulically-assisted for light action. It has rubber-encased, new-type constant-velocity joints and the turning Circle is 36 ft. 1 in.
This new Citroën is a striking, low-hung four-door saloon with plastic (Kraylastic) roof and light-alloy soun-damped bonnet and boot-panels. Bench-seats are used, with arm-rests there is an anti-bump sponge-rubber roll round the inside of the roof, the doors are wide and have ingenious trigger catches, four interior lamps are fitted, two operated by the doors, and the dash contains a lined well-type cubby-hole of great depth, covered by a plastic lid. Curved, rubber-sealed screen and rear window afford extreme visibility, and the driver has, as controls the right-hand treadle-type accelerator, brake “button,” parking-brake pedal and that diminutive finger-tip gear-lever. Before him a horizontal-scale 100-m.p.h. speedometer with trip and total mileometers below, and different colour warning windows for hydraulic pressure, oil pressure and main lamps beam. There is a dial-type fuel gauge. The floor has sponge-rubber undercarpets. Panel lighting is rheostat-controlled and a Continental-style lamps-switch protrudes by the driver’s right hand. The steering wheel is small, and column and single spoke merge, for good instrument visibility and safety in the event of impact.
The lined luggage-boot, with a lid having a telescopic prop and rain-sealing when open as well as when closed, is of 17 cu. ft. capacity, the spare wheel being carried at an angle ahead of the radiator under the bonnet. The dash has a drawer-type ash-tray and there is another huge one for the rear compartment. The windows do not appear to seal effectively but we are assured that air pressure within the car keeps out rain and eliminates draughts. Fresh air is fed to finned grilles at each extremity of the dash, and two separate radiators warm air which can be ducted to the floor of front and rear compartments by operating the appropriate little levers beside the dash. In addition, a fan delivers hot air for screen demisting, the screen having dual washers and wipers. Flashing direction indicators are carried at roof level at the back, clear of the rear lamps, and the head-lamps are naturally in-built.
The road wheels are retained by a single nut and carry Michelin “X” 165 by 140 tyres. To remove a rear wheel the spat-type mudguard has to be removed, but a single nut, undone by the wheelbrace, releases this. Visibility from the driving seat is excellent, as the bonnet drops away to a low-set air-intake, and both front wings are visible. The fuel filler is beneath a flap in the off-side back mudguard. The engine has a compression ratio of 7.5 to 1, plugs “buried” in its valve cover, thermostatic water-cooling and uses S.A.E. 20 Oil. The wheelbase is 10 ft. 3 in., the dry weight 22 cwt., and the 14-gallon fuel tank is under the back seat.
The new Citroën should prove an exceptionally safe car capable of around 90 m.p.h. in unrivalled comfort. Although it is distinctly revolutionary the hydro-pneumatic suspension has been tried on the Six and an automatic clutch on the 2 c.v., and similar hydraulic mechanism was normal on aircraft over a decade ago. Consequently, there is no reason why anyone should doubt the ability of the new Citroën to achieve at least the success of its famous forebear, the Light Fifteen, which has been in successful production for over twenty years in virtually unchanged form. Costing £1,403 12s. 6d. in England, inclusive of import duty and p.t., this new Citroën competes with many medium-sized family cars, while for mechanical ingenuity allied to practicability it is in a class of its very own. It is sure to he in great demand amongst discerning Americans. I must confess that after journeying to Slough to inspect it, I came away feeling that British cars are merely vintage vehicles dressed-up in modern shells. — W. B.