The 300S could not be - and it was not supposed to be - a commercial success, but a label through which Daimler-Benz was presenting its new-born strength. People looking for a replacement for their 540K after the war would find their search successful on the Automobile Exposition in Frankfurt in 1951: That's where Mercedes-Benz presented the brand-new 300 (W186), a definitely noble creation that was worth about DM 20,000 as a sedan and DM 23,700 as a four door convertible (300 Cabriolet D). It was easy to guess this would not become a bestseller: A house was worth just about the same amount of money, and the average income of a worker was DM 61 in 1950. But this new-born star in the automobile skies was far more than a car, it was a clear proof what the German industry and of course especially Daimler-Benz was capable of again.
   But the comparison with the 540K in the introduction does not fit: The supercharged pre-war Benz had been available in sportive, short-wheelbase versions: This was not the case for the 300. Even if the 300 - despite his seriosity and comfort - could be labeled as sportive with his 115HP engine and his excellent driving qualities, it still was an almost five meters long (over 15 ft) four-door car. But only until October 1951, when the two-door version 300S (W188) made its appearance on the Salon de Paris. Not only visitors fell under the charme of this car, the press was also full of enthousiasm: the Swiss Automobil-Revue simply called the car "an automobile of the world elite", that clearly was to be taken as a reference within the manufacture of automobiles. French L'Action Automobile et Touristique exprimed similar thoughts, simply calling the car "a car of international class".
   Indeed, the 300S did not have to stand back behind all the Aston Martins, Delahayes and Talbots. It began with the exterior appearance: An imposing, but harmonic styling with a long hood, rounded fenders and a falling tail. It was not stylish, but decent elegance with a dip of sportiveness.
   The interior was royal: anything that could have been upholstered was covered with leather, and any other area was covered with wood. The dashboard alone was probably worth as much as a small car with its wood and chromes. The clocks kept the driver informed about speed, battery amperes, fuel level, time, water temperature and oil pressure. No question, the perfect manufacture and the equipment with twisting seat backs, additional headlights, additional ventilations and optionally a Becker Nürburg did not leave any wishes.
   Therefore it must have been a pleasure just to take place in this first class compartment - as long as one was seated on one of the opulently upholstered leather seats. Those who had to climb into the back would find it less comfortable, as the 300S had just a small bench seat in the rear. Eventually, this bench could be laid down to give room for additional luggage, even if the trunk was huge. No place for head and legs, a hard seat - a grown-up person would feel like in a kid's seat, which was furthermore plunged into darkness because of the small rear window. Consequently, Daimler-Benz sold the car as a three-seater.
   But in these times, many Coupes and Cabriolets with seductive lines and exquisite interiors were waiting to be bought at dealerships; under these circumstances, the high technical level Mercedes had achieved with the three-litre (184 cui) engine probably impressed even more. If one considered the french "Grand Routiers" of that time, with names like Bugatti, Delage or Delahaye and selling through the achievements of the past, worlds were laying between those cars and the 300S. E.g. the Bugatti 101, presented at the same time as the 300S at the Salon de l'Automobile in Paris, seriously had rigid axles in front and rear! Probably not even the engineers in Molsheim knew who would only consider spending a fortune on such a fossil.
   So the german contribution to upper class automobiles seemed to be a class of its own, although it had some common properties with the Bugatti. For example the chassis frame, the same as was used for the 300 sedans, but shortened by 25cm (10 in.) - which still made the 300S have an impressive wheelbase. A drawback for restorators is the fact that body and chassis were welded together, quite an unusual practice for Mercedes.
   Obviously, technically speaking, the 300S was based on the limousine as well, but with some modifications. The 300S had a ball nut steering gear, a thing that was subsequently fitted to the sedans as well. And as the S suggested a sports car, the propulsion was to be improved also: The six cylinder engine M188, designed by the chief of the technical department Fritz Nallinger and the chief motor engineer Wolf Dieter Bensinger, developed 150 HP DIN at 5000 rpm. A compression brought to 7.8:1 and the use of three Solex 40 PBJC carburettors increased power by 35HP.
   But the engine did not only deliver a lot of power, it also delighted through its modern design. Similar to the 2.2 litre (135 cui) engine from the 220, presented the same year, the three-litre block was made through newest technology. Chain-driven overhead camshaft, Aluminum head with big-sized valves for better flow, and seven crankshaft bearings for a safe and silent running. Thanks to this powerpack, the Adenauer reached 175 km/h (110 mph) - this meant the 300S was one of the fastest german serial productions.
   Its fuel consumption? No potential aquisitor hardly wondered about that. The only thing counting was the fact an 85 litre fuel tank made sure the car had a sufficient range - even if some 17 litres would flow through the three Solex carbs for each 100km (18 mpg). And more, a heated intake pipe was supposed to reduce consumption, while the driver could take account of the fuel quality - through a dashboard switch called "Octane compensator", and the Oil-Water heat exchanger which was integrated in the cooling system would assure the correct oil temperature under any circumstance.
   The frame and chassis were as expected: noble, but without experiments. Trapezoidal wishbones at the front, combined with spiral springs and stabilisators, while a two-piece axle was acting in the rear. The electrically operated additional suspension of the four-door version was omitted as it would have been obsolete.
   The brakes were a critical point: even the shorter 300S had a basic weight of 1750 kgs (3800 lbs), a mass which had to be stopped by firm action of the driver's foot and through four drum brakes. Power brakes were fitted from 1954, they enhanced the behaviour of the car a lot. Interestingly, the 300S came along with 12 Volts electrics and the well-known Mercedes central lubrication system. The 300S also had smaller tyres than the four-door version (6.70 vs. 7.60).
   On the transmission, similar to the sedan as well, the four gear ratios were adapted as well as the rear axle ratio. It was not a "Gran Tourismo", but nevertheless a sportive car; a precise steering and a lot of power made the car an experience to drive; who would wonder, with 23,5 mkg (315 lb-ft) at 3800 rpm!
   The car was available in three different body versions: As a Cabriolet A, Roadster and Coupé. But the price would not made a difference: Independently of the version chosen, DM 34,500 had to be left at the dealership. This made it the most expensive german car in serial production but seducted many celebrities, such as the Aga Khan, Gary Cooper or Cary Grant.
   Over the poduction time, until august 1955, 216 people chose a 300S Coupé, which could be refined with a sliding sunroof (soft). The counterpart was the Cabriolet A, which would have been called a Drophead Coupé by a british couachbuilder, that distinguished itself with a thick and isolating soft top and outside stabilisation bars. Folded back, the top would form a thick cushion at the back, while the roadster would have just a small soft top without outer bars but which fully disappeared in the back of the car.
   From Mercedes-Benz, a hard top for the Roadster was not available, even if the Coupe was nothing else than a Roadster with a hard top welded on. A few 300S owners are known to have had their Coupe converted into a Roadster or vice versa. One 300S owner had coachbuilder Wendler in Reutlingen fit his Coupe with a panoramic rear window, and there's another car known in the club who has this modification.
   But this one was already a 300Sc (W188 II), presented on the IAA in Frankfurt on September 1955. Amount to pay for the "new" 300S: DM 36.500! that made it far more expensive than the BMW 503 - and definitely kept ist title "most expensive german car". But the customers did really get more for the DM 2000 difference: for example swivel windows, additional chrome on bonnet and fenders; many people even felt it was too much of a bit, and felt the designers in Stuttgart had abused of chrome.
   But not only the appearance was changed, but the core as well. The 300Sc was fitted a Bosch fuel injection, allowing 175 HP DIN through a compression increased to 8.55:1. This made the car step over the 180 km/h-line (115 mph).
   This and other technical improvements made the 300Sc a far better car than its elder brother. This had proved to be necessary, as a serious competitor had appeared: the BMW 503, also offering luxury, power and a famous label, plus eight cylinders and a modern ponton-shaped body. Was that the reason the new version of the 300S only found 200 buyers, 98 Coupes, 53 roadsters and 49 Cabriolet A's?
   Another interesting chapter is the activity of some coachbuilders on the 300S chassis. Most significant the work of Italian Pinin Farina, who built the following three:
   Wendler is also known to have made a five-seater coupe based on a sedan. In spring 1958, the production of the 300Sc was stopped, leaving people looking for a special car a little helpless...
   ( mercedes-veterans.com )
More ...