Known articles and Road Tests

The Autocar February 22, 1952 New Cars Described: Post-War Mercedes in Production '...To have repaired the devastation of war and then designed, developed and brought to production these new models is a great achievement, and the unremitting effort involved may have contributed to the death of Dr. Haspel, the managing director of the Daimler-Benz company whose career was recently cut short at the age of 53, just at the moment when he had succeeded in restoring the oldest car factory in the world to a competitive place in international markets...'

The Autocar May 23, 1952 Front page of Offprint from "The Autocar", London, May 23, 1952 as distributed by Mercedes-Benz dealers. '...maintains a high general level of excellence and embodies new technical developments, particularly in suspension and steering, which show clear advantages in comfort, stability and safety.'

Below is reproduction of the text of the report.

The Autocar ROAD TESTS

1467: MERCEDES-BENZ TYPE 300 SALOON

The Type 300, the largest car in the Mercedes-Bent post-war range, has under gone a process of development since the prototypes were first demonstrated at the Frankfurt Show a year ago. On the cars now in production a two-piece propeller shaft replaces the single shaft, the cruciform chassis frame has been heavily boxed in at the centre for extra rigidity and numerous detail improvements have been incorporated.

A Continental test on a production model recently made available by the manufacturers shows that the car now challenges the best produced anywhere in the world today. To the characteristics of high performance, impressive appearance and fine detail finish which distinguished the big Mercedes models of pre-war days are added new virtues of silence, flexibility and lightness of control, while the latest rear suspension, a product of long experience on Grand Prix cars and touring cars, confers a degree of security at high speeds on rough and slippery surfaces whim it would be very difficult indeed to equal.

There are still very few saloon cars which are capable of a mean speed of over 100 m.p.h., but to obtain this result on a five-six-seater saloon car with generous room for passengers and luggage, using an engine of three-litre capacity said to deliver only 114 b.h.p., is a notable achievement. As the weight is some 1¾ tons unladen, it is not to be expected that the top gear acceleration will match that of the larger engined transatlantic cars, but very good results can be obtained by using the all-synchromesh four-speed gear box and the driver is given every encouragement by the steering column change mechanism, which is unusually light, positive and a pleasure to use. Clutch action is light, and it is possible without the exercise of any special skill to reach 50 m.p.h. from rest in 11.7 seconds, or to reach 60 m.p.h. in 11.7 seconds.

The driving position is very good, the back rests of both front seats being adjustable for angle; there is a view of both front wings through the wide windscreen, while the instruments are well placed on an elaborately equipped facia panel. The steering earns special praise. It is extraordinarily light for a car of this size, but requires only three and a half turns from lock to lock. A recirculating ball steering gear is used and the linkage has a hydraulic damper which prevents all road shock being transmitted back to the wheel but preserves the feel of the road and an adequate amount of castor action. The behaviour at high speeds on the open road is beyond criticism, yet the car is easy to park and can be forced along over twisting mountain roads with less effort than is needed for many small vehicles.

The suspension and handling qualities offer a combination of riding comfort, stability and safety which reaches the pinnacle of current achievement, The upholstery, with rubberized hair overlays on interlocking spring cases, may appear a little firm to those accustomed to foam rubber, but it supplies the support necessary on a car with such extraordinary cornering capabilities and no fatigue is experienced after a long day's travelling. The ride is soft enough for the most fastidious passenger, but is very well damped, and there is no sensation of roll, even when travelling really fast over winding roads. Sound insulation is most effective, and the occupants are not made aware of changes in road surface either by roughness in the ride or by marked changes in the noise level. When cruising at speeds up to 70 m.p.h. there is practically no noise except the whisper of wind and tyres, At 80 m.p.h, the wind noise increases, but it is possible to carry on normal conversation or enjoy the excellent radio at speeds up to over 90 m.p.h. However fast the corners are taken, the tyres hardly even squeal. There is no noticeable tendency to understeer or oversteer; if forced to the limit, the rear end will begin to slide, but in a way which is instantly controllable by a flick of the wheel.

In searching conscientiously for something to criticize, one might remark on a slight high-speed vibration period, but as this seems to occur at nearly 100 m.p.h. it is not likely to mar the pleasure of most users, On slimy surfaces or on wet tramlines, the experienced driver will have to search hard for a parallel to the sure-footed disdain with which the Mercedes-Benz maintains its cruising speed.

When heavy loads of passengers and luggage are being carried, a switch on the facia operates a servo motor which brings auxiliary torsion bars into action in the rear suspension. These are not required for normal loads of up to four people, and indeed they slightly impair the exceptional cornering powers if used with a light load, as they force the rear wheels to adopt a slight positive camber.

This is a car which has no natural cruising speed. It is designed to sustain anything up to its maximum speed as long as road conditions permit, and in the course of the test it was run continuously for 30 or 40 miles at a time at speeds between 80 and 95 m.p.h., with frequent bursts of 100 m.p.h., without any adverse indications in operating temperatures or pressures. Deep water jackets, thermostatically controlled oil cooling, copper-lead bearings and a hardened crankshaft are among the engine features incorporated to ensure reliable service under prolonged hard use.

Some critics have felt that the braking area available appeared on paper to be small for a car of this weight and commanding performance. During the road test carried out by The Autocar, extending over some 500 miles of fast motoring, no cause for this criticism could be found. Indeed, the brakes three times recorded one hundred per cent efficiency on the meter, the third occasion being the tenth in a long series of "crash" stops, the average results of which are recorded in the tabulations. The brakes were subsequently used hard in high-speed main road motoring and deliberately abused on a mountain descent without producing fade. These are remarkable results and need no apology. Moreover, the brakes proved unusually safe when used hard on treacherous surfaces. Moderately heavy pedal pressures proved desirable in stopping from high speeds, but gave no advantage at low speeds, and excessive pressure locked the rear wheels.

In every detail of finish and equipment the car gives evidence of quality. The doors close easily with the smooth click of special locks which are mounted in rubber. Facia and window fillets are in polished wood and the equipment is so full that it can be reviewed only briefly. The horn ring can be turned to operate the flashing direction indicators and a tell-tale light on the facia tells the driver when they are operating. A switch under the facia brings in a third horn to supplement the usual pair for really fast motoring. There are four ashtrays, two on the facia and one on each rear door, which empty themselves into a lower container each time they are used, and the facia carries a cigar lighter.

Lubrication of the chassis, including the centre bearing on the divided propeller-shaft, is attended to by a one-shot system operated by pedal. The heating and ventilating system is unusually complete. Fresh air intakes above the radiator supply ducts leading to two heat exchangers on the scuttle and selectors on the facia enable warm or cold sir to be directed to the screen, the side windows, or the feet of the passengers as required, with a fan for use when the car is stationary. The radio installation has two loud speakers in front and a further two can be switched on in the rear when required. Other items include an accessible fuel tap with reserve position, rheostat control for facia lighting, electric clock, screen spray, prismatic anti-dazzle mirror, and a combined ignition and steering lock. A lock is also provided for the doors covering the fuel filler. There are unusual ventilating panels on the doors, which hinge inwards, preventing draughts when the main windows are open. The big head lamps give an excellent beam, adequate for travel up to about 80 m.p.h.

Apart from the large luggage space at the rear, provision for small packages includes a lockable glove box, large containers in the front doors, and a big shelf behind the rear seats. An interesting item of interior equipment is a rail over the doors which can be used as a hand grip by the passengers when the car is cornering very fast, but also carries small coat hooks, which are a boon in hot climates.

The Type 300 Mercedes-Bent is clearly a very strong competitor for the favour of the most discerning international buyers, to whom it will appeal because of its performance, detail finish and equipment. It maintains a high general level of excellence and embodies new technical developments, particularly in suspension and steering, which show clear advantages in comfort, stability and safety.

-----------------------------PERFORMANCE------------------------------------------

Mercedes-Benz Type 300 Saloon

ACCELERATION: from contstant speeds. Speed, Gear Ratios and time in sec.

From rest through gears to:

Standing quarter mile, 20 sec.

SPEED ON GEARS:

TRACTIVE RESISTANCE: 35 lb per ton at 10 M.P.H.

TRACTIVE EFFORT

BRAKES:

FUEL CONSUMPTION:
15.5 m.p.g. overall for 260 miles. 18.5 litres per 100 km.
Approximate normal range 15--20 m.p.g. (18.8--14.1 litres per 100 km).
Fuel: German normal, 70--72 octane.

WEATHER: Dry, medium sidewind. Air temperature 70 degrees F.
Acceleration figures are the means of several runs in opposite directions.
Tractive effort and resistance obtained by Tapley meter.
Model described in The Autocar of February 22, 1952

SPEEDOMETER CORRECTION: M.P.H.

------------------------------------------DATA-------------------------------------------------

PRICE: (basic), with saloon body, DM 19,900 =£1,695 at DM 11.78 =£1.
Not obtainable in Great Britain.
Extras: Radio DM 900.
Heater standard equipment.

ENGINE: Capacity:2,996 c.c. (185 cu in).Number of cylinders: 6.
Bore and stroke: 85 x 88 mm (5.95 x 3.47 in).
Valve gear: Single overhead camshaft.
Compression ratio: 6,4 to 1.
B.H.P.: 114 at 4,600 r.p.m. (B.H.P. per ton laden 60).
Torque: 145 lb ft at 2,500 r.p.m.
M.P.H. per 1,000 r.p.m. on top gear, 18,4.

WEIGHT: (with 5 gals fuel), 34 2/3 cwt (3,874 Ib).
Weight distribution (per cent) 52.4 F; 17.6 R.
Laden as tested: 38 ¼ cwt (4,288 lb).
Lb per c.c.(laden): 1.4

BRAKES: Type: F, 2-leading shoe: R, leading and trailing shoe.
Method of operation: F, Hydraulic. R. Hydraulic.
Drum dimensions: F, 10 ¼ in diameter, 2 ¾ in wide. R, 10 ¼ in diameter, 2 ¾ in wide.
Lining area: F, 97 sq in; R, 97 sq. in (101,5 sq in per ton laden).

TYRES: 7.10-15 in.Pressures (Ib per sq in) : 25 F; 28 R (normal) 29 F ; 32R (for fast driving).

TANK CAPACITY: 15.85 Imperial gallons.Reserve 1.3 gallons. Oil sump, 11 pints. Cooling system, 35 pints with heater.

TURNING CIRCLE: 39ft O in (L and R),Steering wheel turns (lock to lock) : 3 ½

DIMENSIONS: Wheelbase 10ft O in.Track: 4ft 8 ¾ in (F) ; 5 ft O in (R).
Length (overall) : 16ft 3in. Height: 5ft 3 in. Width: 6 ft 0 ½ in.
Ground clearance: 6 7/8 in. Frontal area : 25.3 sq ft (approx)

ELECTRICAL SYSTEM: 12-volt, 50 ampere-hour battery.
Head lights: Double dip, 35 watt.

SUSPENSION: Front, independent, with coil springs, wishbones and anti-roll bar.
Rear, independent swing axles and coil springs, with auxilary torsion bars.

The Practical Classics, October 1983 Salon Feature: The Mercedes Benz 300 '...There are some cars - perhaps a mere handful - which exude a seemingly magical appeal: which, on first sight, you know you have to learn more about them...' ' it was the sheer opulence and style of the 300 saloon that made it so remarkabe in its time...'

Comments and queries to: Stuart Lamb