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When former rivals Benz & Cie. and Daimler-Motoren-Gesellschaft entered into a community of interest in May 1924, one of the main tasks facing the new management was to standardise and modernise the product range. Amid efforts to create an attractive, modern and competitive range of passenger cars, the development of a new two-litre model was of particular importance.
In the economically challenging times of the 1920s, an appealing, reasonably priced automobile was essential for winning market share in the potentially lucrative mid-size segment.
In spring 1924, alongside the two luxury-class models with six-cylinder supercharged engines, DMG was also developing a third model which, although designed according to similar principles, was not yet as far advanced as the large-capacity models with 4.0 and 6.3-litre displacements.
Likewise featuring a six-cylinder supercharged engine, it was designed to produce around -40_hp from its two-litre displacement, and as much as 60_h- with the supercharger in operation.
Already at the initial board meetings of the community of interest in May, the two‑litre car was the source of heated debate. While DMG had planned to produce its small supercharged model in Mannheim, Friedrich Nallinger from Benz & Cie. doubted that the technically complex and expensive supercharged vehicle was capable of securing jobs at the Benz parent plant. Apart from that, Benz had already completed the design of a naturally aspirated two-litre swing-axle model. Nallinger proposed that the new model planned for Mannheim should come with a choice of two‑litre or 2.6‑litre engine.
In November 1924, the situation escalated. The Mannheim contingent claimed that the Untertürkheim design was not suited to the existing manufacturing facilities and would make production considerably more complicated and costly.
A sales price of RM 15,000 for the two-litre model was not realistic, it was argued, at least not based on a production volume of around 500 vehicles per month. Consequently, whereas Benz’s objective was to achieve high unit sales through low prices, what DMG had in mind was a technically sophisticated, and commensurately high priced automobile.
It was January 1925 before signs of a compromise emerged between these diametrically opposed standpoints. Benz resolved to build not the two-litre car, but a 2.6‑litre side-valve model. However, DMG was to complete its development of the two-litre overhead-valve model in order to allow the start of production at a later date. By decision of the Board of Management in January 1926, the 2.6‑litre project was turned into a three-litre model, which was unveiled at the end of October as the Mercedes-Benz 12/55 hp.
The two-litre project had actually been resumed in July/August 1925, albeit under different circumstances than originally planned: in the months that followed, it became clear that Benz’s long-standing preference for a low-cost model was the correct strategy, and the work on design was initiated at top speed. Whereas it had still been planned in September 1925 to market the open tourer at a price of RM 10,000, by January 1926 the cost target had been reduced to RM 6500 – less than half the amount projected for the original supercharged model.
In August 1925, it was still unclear whether the two-litre automobile should be powered by a four or six-cylinder engine, the initial preference evidently being for four cylinders. Three months later, it was decided to design a six-cylinder unit as an alternative to the four-cylinder engine, and to install this engine in an experimental vehicle.
At the end of February, the four-cylinder model, then still known as the 8/35 hp, was expected to enter its testing phase in July 1926. Unfortunately, there is no detailed account of the reasons that ultimately led to the decision in favour of the six-cylinder engine.
The new two-litre automobile broke as little technological new ground as the three-litre model built in Mannheim. Chassis configurations with front and rear rigid axles, and six-cylinder side-valve engines were conventional technology at that time. Although lacking any special technical refinements, both models ranked as rugged, reasonably priced automobiles of high quality.
The two new models were unveiled in October 1926 at the Berlin Motor Show, the first appearance at a motor show of the newly merged Daimler-Benz AG. Developed by the joint venture, they were the first passenger cars to be marketed under the new brand name of Mercedes-Benz.
The first two series-produced chassis of the two-litre model were built in Untertürkheim in October and November 1926. Rising to 24 units in December, monthly production reached 270 units in March 1927, in good time for the start of delivery. In spite of some initial difficulties, the two-litre passenger car was an instant success, it alone selling over twice as many units in 1927 than the sum of all Mercedes, Benz and Mercedes-Benz models produced in 1926.
The two-litre six-cylinder engine M 02 had tremendous future development potential. In several stages over a period of 12 years, it provided the basis for higher-displacement engines for subsequent generations of passenger cars: the M 11 of 1928 with 2.6 litres, the M 18 of 1933 with 2.9 litres and, finally, the M 142 of 1937 with 3.2 litres and later 3.4 litres.
The progression of the model designations and in-house design codes reflects the changing situation in those years, which today often still leads to misunderstandings. In accordance with common practice, the two-litre model was named the 8/38 hp at its launch, the first figure standing for the displacement-based fiscal hp and the second for actual engine output. The in-house documentation initially still used the design code W 6506 – a designation that conformed to the traditional DMG system.
Whereas this W‑number was based on the bore/stroke dimensions and number of cylinders of the engine, the new W-codes introduced with the inception of the Daimler-Benz era were more or less just consecutively allocated design codes devoid of any deeper meaning. Under this classification system, the 8/38 hp was given the in-house code W 02. After the 5/25 hp prototype W 01, therefore, it was the second model to which the new numbering system was applied.
In February 1928, the sales codes of Mercedes-Benz models were also brought up to date, with a three-digit number being added to the traditional hp designations that had been used for almost two decades by all manufacturers. The value of the additional number, multiplied by ten, gave the rounded displacement of the engine in cubic centimetres. Thus, the 8/38 hp mutated into the 8/38 hp 200 model.
Whereas engine data and fiscal hp have long since ceased to provide the basis for model designations, the three-digit number introduced in early 1928 has, with certain additions, been retained to this day in the model designations of Mercedes-Benz passenger cars.
At the start of sales, the new entry-level model with the designation 8/38 hp was available in three different body versions: as an open tourer and a two- or four‑door saloon. In April 1927, the range was extended to include two 2/3- and 4/5‑seater special convertibles. Alternatively, customers also had the option of ordering the chassis for coachwork to be added by one of the numerous coachbuilders. Six months later, the product line-up was yet further extended: the four‑door saloon was now additionally available with a partition or as a special vehicle for doctors and hospitals; a further option was a four-/five‑seater landaulet.
In February 1928, alongside the new designation 8/38 hp 200, some additional measures were taken to promote sales. These involved lowering the sales price and widening the choice of body to a total of eleven variants. The newcomers were a two‑seater sports car, a landaulet with open driver’s seat and a pullman landaulet. In July, the range was further extended to include a four-/five-seater short special convertible and a version of the four-door saloon with six windows. The number of available body variants rose to 13.
However, 1928 meant more than just reduced prices and wider choice as far as the 8/38 hp was concerned: the car was also given a radical facelift under the direction of DrHans Nibel. Having already enjoyed parity of status next to Porsche during the period of the joint venture, the former chief designer at Benz & Cie. was appointed Porsche’s successor in early 1929. The facelifted version was unveiled in November 1928 at the International Motor and Motorcycle Show in Berlin under the new name of Stuttgart 200. Internal documents from that time occasionally also make reference to the 200 Stuttgart.
The new model designation, doubtless more appealing than the rather dry 8/38 hp, related to where the vehicle was produced and was inspired mainly by the name of the new eight-cylinder model that had been launched one month previously as the Nürburg 460. This new model owed its name neither to its production location nor to its distinctly sporty character, but to the fact that it had successfully undergone endurance testing on the Nürburgring. One year later, the name of the three-litre vehicle, which by now had a displacement of 3.5 litres, was brought into line with the new nomenclature and changed to the Mannheim 350.
From early 1929, following the facelift, the range of available versions of the Stuttgart model was extended yet again. Although the variety of bodies had been brought back down to a manageable number, there were different equipment packages as well as an additional engine variant, the 10/50 hp Stuttgart 260.
The job of the new 2.6‑litre model, known internally as the W 11, was to fill the gap in the passenger car sales programme between the 200 and 350. The two-litre model had served as the basis for a vehicle with a significantly more powerful engine which, while satisfying the growing demand for performance, continued to be competitively priced.
The M 11 engine was based on the by now established two-litre unit, the sole change being that the bore had been increased by 9 mm to 74 mm. Like its lower-displacement twin brother, the Stuttgart 260, although conservatively designed, made a good name for itself thanks to its reliability and ruggedness.
Both engine variants were available not only in a wide range of bodies, but also in two different equipment packages. In terms of equipment level and appearance, the so-called “special” version of the two-litre model corresponded to the previous 8/38 hp 200 model. In addition to the four-door saloon with six windows, the range of bodies included the four-/five‑seater open tourer, the two-seater sports car and the familiar convertibles, which were now officially called Convertibles A, B and C.
The saloon and tourer were alternatively available in a so-called “standard” version, which cost RM 200 less and was obtainable only in a limited choice of four paintwork and four interior equipment variants. It was the only version of the “Stuttgart” model range to have a finned-tube radiator instead of the otherwise customary honeycomb radiator. There were also differences with regard to the instrument panel: there was no clock and the speedometer was of the scrolling type. Both versions of the Stuttgart 200 came without bumpers and had black-enamelled window frames as well as black-painted wheel discs and headlamps. Luggage was accommodated on a rack at the rear of the vehicle.
The Stuttgart 260 was available in the same range of variants as the two-litre model. The “standard” version of the higher-displacement model was additionally equipped with the honeycomb radiator, the two-seater sports car being available only in this basic version. The better-equipped variant of the 260 model was called the “luxury” version. Exterior signs of the superior equipment level included nickel-plated bumpers, hub plates, window frames and headlamps. The radiator cap and headlamp connecting rods were likewise in polished metal.
The instrument panel was more comprehensively equipped with the conventional speedometer as well as the standard clock, and the rear luggage rack featured a large trunk with a smaller trunk inside. The standard equipment also included protective spring gaiters. High-grade fabrics were used in the interior. The choice of interior fabric as well as the colour of the paintwork could be specified according to the personal preferences of the customer.
Production of the Stuttgart 260 started in September 1928 and reached volume production level in February 1929, at the same time as manufacture start-up for the standard version of the two-litre model. Despite being taken out of production in April, the Stuttgart 200 Special was included in the price list of November 1929 – at least in its two-seater sports car, tourer and Convertible A versions. Reducing the two-litre model to the standard version made every sense, as the more luxurious and sportier variants undoubtedly benefited from the enhanced power of the 2.6‑litre engine. This also found expression in the production statistics: in the year of its launch, the Stuttgart 260 reached a volume of 3640 vehicles, considerably more than the precisely 2000 units of its two-litre counterpart.
In November 1929, the four-seater, four-door Convertible D version of the Stuttgart 260 replaced the previous two-door Convertible B and, at a price of RM 10,600, became the most expensive variant of the model series. In February 1930, both engine versions of the two-seater sports car were dropped from the range. At the same time, the “standard” version was renamed the “normal” version, and the “luxury” version of the Stuttgart 260 became the “special version”. From August 1930, all Stuttgart models were optionally available with a Mercedes-Benz/Maybach overdrive at an extra cost of RM 575. Engagement of the overdrive gear, which reduced revolutions in the direct gear by 30%, was vacuum-assisted with no need for the clutch.
In February 1931, both models became additionally available in a four-seater, two-door Convertible NC version. The sale price of all variants of the Stuttgart 260 were reduced, and the Convertible A of the special version was discontinued. April 1932 saw a further price reduction, which this time included the two-litre model. The only model not to be included was the Model 260 saloon in the normal version.
Although the life cycle of the Stuttgart model was nearing its end, stylistically modernised forms of the saloon and convertible NC were unveiled in October 1932. The saloon now sported a longer engine bonnet, slightly raked windscreen and flowing lines. The Convertible NC, which, together with the Convertible D, had already been given a raked windscreen one year previously, now featured a continuous chrome trim strip as well as doors with a lower top edge.
In 1933, the range was extended to include a long version of the 260 with a 270 mm longer wheelbase. Between March and October 1933, 50 vehicles were produced, almost all of them in the form of pullman saloons.
The passenger car variant of the Stuttgart 260 was manufactured until May 1933. In July 1934, a further 45 chassis units were produced. Production of the two-litre model came to an end in April 1933, shortly after the considerably more advanced swing-axle 200 (W 21) had been launched as its successor. Nevertheless, a final batch of 50 vehicles was built between July and September 1933. As is made clear by the price list from February 1933, both models, predecessor and successor, continued to be available side by side fpr a while – with the Stuttgart models being yet further reduced in price. The pullman saloon on the long 2.6‑litre chassis figured in the price list until September 1934, the chassis with or without overdrive even being included for two years after that.
The rugged basic design of the 8/38 hp allowed it to be used also as a delivery van chassis, which was available from October 1927 under the code L 3/4. The seemingly unusual name was consistent with the nomenclature for commercial in use at that time for commercial vehicles and stands for a payload of 3/4 tonnes.
With an especially long wheelbase of 3250 mm, this chassis was employed mainly for delivery vans, ambulances and buses. Bus operators used these vehicles to offer excursions for small groups, either with an eight-seater closed body or with an open soft-top body known as “panorama carriage” with ten seats.
Another interesting variant was the “combination carriage”, which had the appearance at first glance of a six-/seven‑seater open tourer. However, once the middle and rear rows of seats had been removed, the vehicle could easily be converted into an open delivery van using a zinc insert. A familiar sight was the “rural postal carriage”, several hundred units of which were in service in the 1930s to ensure postal services in rural areas.
Technically, the L 3/4 chassis was broadly the same as its passenger car counterpart. Behind the rear wheels, however, the longitudinal frame members did not turn down to meet the spring shackles, but continued horizontally. Between transmission and differential, there was no torque tube as on the passenger car versions, but an exposed universal-joint shaft, which transferred the power to the rear wheels via a worm drive on the underside of the differential housing.
The first two experimental units of the L 3/4 chassis were built in October and November 1927. Series production began in February 1928 and carried on initially until July of the same year, during which time 103 chassis units were produced with the two-litre engine. In October, the L 3/4 was changed over to the higher output 2.6‑litre engine.
At the International Motor and Motorcycle Show in Berlin in November 1928, Daimler-Benz unveiled an L 3/4-based delivery van and hotel bus, both of which were powered by the M 11 – two months before the Stuttgart 260 appeared on the market. Series production of the 2.6‑litre chassis had already begun in October. In July 1929, the L 3/4 chassis was modified for a payload of 1000 kg and consequently renamed L 1000. It was marketed as the Mercedes-Benz “Express”. At approximately the same time, the L 3/4 or L 1000 was given the internal design code W 37. From February 1933, the L 1000 was also available with overdrive.
The November 1929 price list included not just the chassis, but also a number of bodies: two different platform vehicles, two omnibus variants for 8‑10 passengers with rear or side entrance, and a panel van of “ideal, rugged construction”.
In an attempt not to scare off potential customers with the high price of the bodies, the above-mentioned price list stated: “The same bodies in a simple, lightweight construction are alternatively available from third-party sources at a lower price.” To illustrate the differences, it was further stated: “Please make particular note that our special platform bodies are of particularly beautiful design and the product of particularly sound and careful workmanship. The excellence of our platform bodies does not allow comparison with similar bodies of third-party manufacture.”
Unfortunately, it is not known how many customers were attracted by the particularly beautiful design of the platform vehicle. At any rate, the total production volume of the L 1000 is remarkable, 2 376 units coming off the production line in Untertürkheim between October 1928 and August 1936.
From August 1934 to December 1935, 1507 chassis units for the bucket-seat Kübelwagen were additionally produced on the basis of the Stuttgart 260. Some of the bodies were built at the Sindelfingen plant, while others were made by Trutz in Coburg and Gaubschat in Berlin, the bodies from Sindelfingen accounting for around one third of the total number.
The spoked steel wheels on the normal models were replaced on the Stuttgart 260 Kübelwagen by disc wheels. The vehicle was equipped with an Aphon transmission, which – in line with intended use – could not be combined with the otherwise available overdrive. The Kübelwagen variant of the Stuttgart 260 was highly valued by the Reichswehr on account of its ruggedness. Some examples continued in service until the early 1940s.
Total production of the passenger car version came to 9105 units for the 8/38 hp, 6452 for the Stuttgart 200 and 6757 for the Stuttgart 260. Even though such unit volumes may appear modest by today’s standards, the W 6506 / W 02 / W 11 model family achieved considerable success in its market segment. All three models were manufactured in Stuttgart-Untertürkheim. Anyone referring today to the Stuttgart model will normally mean the entire model family, even though this name was introduced until the facelift in autumn 1928.
Source: Daimler Media