New cars: Mercedes 190
A new class for Mercedes
It took ten years — three more than is usual in the motor industry — for Mercedes-Benz to design and produce a more compact model than their traditional customers would expect, and for much of that time the arrival of the W201 series 190 and 190E has been keenly anticipated and debated.
We now know that smaller does not mean cheaper in any sense of lower quality, and neither does it mean that any of the traditional virtues have been dispensed with. The 190 series is 30.5 cm shorter than the W123 series, 10.8 cm narrower, 5.5 cm lower, and is no less than 270 kg lighter; the reduced drag factor of 0.33 further assists in achieving good fuel consumption, the realistic "composite average" of which is around 33 miles per gallon.
Motor Sport was invited to Germany before the UK launch in September to drive the 190 series and to visit the ultra-modern Sindelfingen production plant where 1,800 cars are produced every day; the added production at Bremen in northern Germany, around 500 per day, will bring the German company's daily production up to around 2,300 cars, a rate of over 500,000 per year. Not bad for a range that starts at DM28,000 in Germany, and will start at about £10,000 tax-paid in Britain.
To begin with the range consists — as it has for the German market this year — of the 90 bhp carburated version or the 122 bhp Bosch fuel injected version, with four-speed automatic or manual transmissions, or a five-speed manual box. A Diesel will be added to the range by the end of this year, and in the meantime we expect some higher performance models to have been on display at the Frankfurt Show, the most potent of which has a Cosworth designed and built 16-valve cylinder head on the alternative 2.3-litre engine. All the same, Daimler-Benz AG have no sporting aspirations at the moment, and if they homologate the model it will be to please their customers more than anything else.
For now we are concerned only with what we can buy, and that's good enough for a whole new clientele. In Germany, DB would on the whole prefer not to sell a 190 to an existing customer and a consequent rating of 60% is highly satisfactory. The company has aimed for, and reached, a younger generation of customers — and if we can believe the claim, stated seriously, that 97% of customers buy another Mercedes, the 190 must be the most important model ever launched. The average length of Mercedes ownership is four years, and the fact that almost 50% of the company's employees have bought the products at a 20% discount proves that loyalty begins at home!
Viewed from any angle the Mercedes 190 retains the characteristic handsomeness found across the range, extremely carefully blended so as to make it look a bigger car than it really is. The roofline takes an almost imperceptible downward turn towards the back, leading the airflow onto the convex boot lid. The front screen is wiped by a single, centrally mounted blade of fairly massive proportions, and we gather that rain channels are fitted "despite the drag created" in the interests of keeping the side windows clear, for extra safety.
Absolutely no sacrifices have been made in space, feel or quality insofar as the driver and passenger are concerned; to sit in, look at, and drive, it could only be a Mercedes. The comment has to be qualified, however, in that rear seat accommodation is somewhat limited, an that if the front seat occupants are long-legged two adults would be cramped for legroom in the rear. Neither is the headroom particularly generous in the back, a six-footer just about touching the rooflining, so from the outset the 190 has to be regarded more as a young family car.
Full credit must be given to Mercedes for producing one of the most refined 2-litre, four cylinder engines we have ever come across. Good mountings and insulation are part of the design package, of course, but within limits the engine, rated at 90 bhp in carburated form or at 122 bhp with Bosch K-Jetronic injection, is excellent. Only at high engine speeds is there any hint of harshness, and we suspect that the cars will rarely be driven in that realm.
The carburated 190 has acceleration best described as steady, going to 60 mph in 13.2 sec and on to a top speed of 108 mph, though with four forward speeds the automatic is little slower, 60 mph taking 13.8 sec and the top speed being 105 mph. With injection, the 190E is much more impressive reaching 60 mph in 10.5 sec (auto 11.0 sec) and attaining a top speed in fourth gear of 121 mph (auto 118 mph).
Fifth gear is a real overdrive at 0.78, the first four ratios being the same as in the four-speed box and rather widely spaced, though we learned that second is being raised to narrow the gap. In fifth, 70 mph is achieved at a mere 2,600 rpm, and at maximum speed 4,500 rpm shows on the tachometer, indicating just how quietly and economically the car is running. The automatic 'box is probably going to be favoured by most customers, though, with no little sacrifice in performance or economy. There is an Economy setting control by the lever which locks out first gear and tells the 'box to shift up at lower engine speeds, which seems like the best of both worlds.
We have said nothing yet of the suspension, of which the Mercedes engineers are particularly proud. Dr Kurt Enke, head of passenger car project design, described the five point multi-link independent rear suspension in this way: "I am convinced, never in the past and perhaps never in the future will you find a suspension development of such dimensions yielding such a big step forward to the very limits of physics. It surely deserves its own page in the book of automobile history."
That is a pretty strong claim for a German company, having grappled with the problem of making the suspension just as supple as the heavier range of cars without sacrificing ride or handling. The handling quality perhaps took first place, for the chassis feels extremely developed even when driven well beyond the normal bounds, while the ride comfort remains above average for the class. To be critical, the ride is not quite as soft nor as quiet as in the S-class cars, though the overall package is near to ideal for the target group of customers. Eight basic designs and no fewer than 70 variations were considered, about a third of these being tested in a buggy device with interchangeable front and rear suspension subframes.
Our introduction to the Mercedes 190 is longer than usual because it is one of the most significant new cars to appear in this decade. Six hundred will be imported to Britain this autumn, 2,800 next year and 5,000 the year after, and we can take it for granted that the demand will generally exceed the supply. - MLC.
Although Cosworth in Northampton and Mercedes of Unterturkheim began work together on a proposed 16-valve engine for rally work during the late seventies, the 185 bhp motor and what Mercedes describe as potentially the fastest car in their production line owes most to "serious development work since October 1982". As part of a programme that was publicly unveiled at the Frankfurt Show, which provides for production of the sporting Mercedes 190 2.3-16 from June 1984 onward, the factory also ventured to the Southern Italian Nardo test track, returning with three new outright World Records and six class records. Currently awaiting FIA recognition, the average speeds set were in a tight bracket from 246.628 km/h to 247.939 km/h, approximately 153.156 mph to 153.970 mph.
The speed was averaged over 50,000 km (31,050 miles), reflecting the ability of these modified production prototypes to reach up to 165 mph on the 12.64 km banked track. Mercedes' successful assault was on records that had stood below 112 mph since Ford established them at Bonneville salt flats in 1956. However happy the marketing and PR men at Mercedes may be over the record breaking aspect, the factory engineers were really only seeking high speed proof of the endurance capabilities of their 16-valve four cylinder as part of practical research and development which also covered trials in Death Valley, USA, the Arctic Circle and the Sahara Desert.
To understand M-B's development angst, they recalled that three prototype 190 2.3-16s had striven for these international records. Effectively two were trouble-free over 50,000 km changing drivers every 21/2 hours, refuelling without a change of Pirelli 205/55 - 15 slicks on 7J Pirelli aluminium wheels in 18-28 sec, or taking from 3 min 30 sec to 4 min 30 sec for a complete compression and valve clearance check, plus new tyres and an oil change!
The third car did run into distributor trouble - and such parts were not amongst the array carried on board in the rear passenger seat - so former rally manager and present day future engineering project manager Erich Waxenberger had to "stick together parts from two distributor arms" before the car could proceed, eventually to average over 242 km/h (150 mph). We asked M-B development chief Prof Werner Breitschwerdt what lessons for the production car (of which 5,000 are planned in the first 12 months production, qualifying for international Group A competition) had come from record breaking and other activities? The response immediately centred on "modifications to the distributor fingers, but we have also learned of changes that had to be made to the valves, rings and other engine parts during earlier development".
Nardo's suitability for running speeds over 150 mph without strain also allowed Mercedes to investigate a modification of the existing uprated 190 independent suspension, that incorporates inter-connected front and rear Mercedes load levelling hydropneumatic systems. These equipped the record breakers and we tried one prototype with ± 15 mm (0.59 in) body ride height adjustment "in-flight". Naturally there are benefits to handling and aerodynamics at the lowest ride height and M-B engineers say that adjustment of rear ride height is "definite" for production, with full front and rear hydropneumatic control via a cockpit switch "a likely option" in Waxenberger's opinion. It is thought production 2.3-16s will have a Cd figure of 0.31, in contrast with the 0.30 quoted for the record breakers. These had a radiator blind facility that "made everything better," in Waxenbergers' tongue- in-cheek assessment. "For it took kilogrammes off our drivers in the heat, because they couldn't use the cooling with the blind closed. They got lighter and the cars were faster .... !"
Quite why Mercedes are allowing journalists to drive a vehicle nine months before its anticipated production date - with no guarantee that we will ever receive even LHD examples in the UK - is officially a mystery. It seems most likely that Mercedes want to demonstrate sporting potential in their range because of the publicity currently accruing to Audi, Porsche, BMW and Opel through their competition forays from German bases. It will be remembered that Mercedes were involved in World Championship rallying using the talents of Hannu Mikkola and Bjorn Waldegaard until 1980, when there was an embarrassing volte face following the employment of German World Champion Walter Rohr!. Then it was said that they would return with "the small car," which became the 190 range, of course. However, there is no sign of an official return, although another 100 bhp and 200 kg less weight in the 2.3-16 is envisaged for Group A saloon car racing by private teams from Summer 1985 onward.
As to the cars we drove on a welcoming Hockenheim track - they had removed all the usual chicanes, so we could cruise past Schikane 1 at nearly 130 mph - they provided exactly the intended appetizer.
Engine details that have been released included the provision of a 10.5:1 cr within the Cosworth pent-roof cast aluminium cylinder head which employs twin overhead camshafts that are driven via a 20 mm wide, "conically ribbed belt". Incidentally Cosworth are credited primarily with co-development and casting the head, plus machining it partially. Mercedes expect to duplicate some 'head work under licence eventually. Either way Cosworth are expected to supply at least half the cylinder heads sold. The iron block carries identical 99.5 x 80.25 bore and stroke to the present 230E to produce 2,299 cc. Planned production power, provided on most of the vehicles tried, is 185 bhp at 6,000 rpm and 240 Nm torque by 4,500 rpm; maximum safe rpm are 7,000.
The lack of pre-Frankfurt Show detail on items such as precise description of the four-wheel disc braking system, five speed gearbox and other suspension modifications, aside from the ride height adjustment was understandable, although we were told that the Mercedes-designed, Sachs manufactured, system of gas shock absorbing would be employed. Yet everyone can see the multiple spoilers and extended side bodywork. The latter is distinctly in the AMG-modified style in high quality glassfibre, and shows that Mercedes would like a share in the increasing market for the performance car styling sold to thousands of their customers every year.
Whether in bumpy and occasionally rattly record-breaker trim without the planned power steering, or as pristine as a showroom seductress, the test examples left behind an outstanding impression. The engines are crisp in the Cosworth mould above 4,500 rpm, reaching for 7,000 rpm and 93 mph in third (or 124 mph at the same rpm in fourth) with enjoyable speed. You can also accelerate from 1,100 rpm in fifth, but there is a notable bonus in driveline smoothness beyond 2,000 rpm in top, and you would normally drive between 3,000 and 6,000 rpm in Mercedes smoothness, with 139 mph the slowest speed indication from our test quartet. Utilising Pirelli slicks (albeit in the anticipated production sizes given earlier) on a race track we could not judge ride or cornering capability in production trim. We do know that the car delivered all the oversteer balance needed for bracing race track slides, and that it always stopped tidily, albeit smokily, from speeds of over 130 mph. The 2.3-16 Mercedes 190 promises to be one of the last no-nonsence performance cars. No turbochargers or 4-wheel drive were needed to provide what feels like a taut and immediately responsive sports saloon. Even at the usual wallet-tingling Mercedes Benz (United Kingdom) Ltd prices it could expect a warm welcome in Britain. - JW