Musings

 Mercedes 560 and beyond — Leaving the perils of agitated Subaru owners and all-wheel-drive behind him, our musing monthly writer drives the latest in British offerings from Mercedes-Benz at 150 mph speeds. Taking the opportunity to talk to the factory’s engineers and chief development driver about intriguing developments of the three pointed star’s mystique.

The view is a beautiful one for lovers of shared speed. Ahead, leading 203 inches of the latest in Mercedes-Benz V8 machinery, the glinting chrome of the Daimler-Benz star. Adorning the £47,225 SEL 560 saloon, the star’s centre point is employed to aim one and three-quarter tons of four door saloon at the 2.02 mile upper band of General Motor’s Millbrook proving ground.

We are running raised tyre pressures, but otherwise the same standard 300 brake horsepower and 334 lb ft of torque that lazily murmured its assistance on the road to the track.

The aluminium encased 5547 cc (96.5 x 94.8 mm) with an overhead camshaft topping each vee bank is redlined at 6100 rpm, which means we are exceeding Britain’s overall speed limit in only the second ratio of the Mercedes manufactured and designed automatic quartet.

Third is utilised as we ascend the banking at two miles per minute, another swift and smooth shift (ignition timing is automatically altered to lower torque during the gearchange for durability and civilisation reasons) taking us towards the target of the company’s maximum speed claim: 155.25 mph.

Inside the steel body is not the usual testing crew of one or two persons, but three adults watching a fourth at work, knowing that their futures depend on his actions. Concrete blocks rushing beneath 215/65 radials seek to disturb the artificial calm within that walnut-appointed cabin.

Andrew “Marathon Man” Cowan, farmer of more than 700 Scottish acres, owner of three previous S-class Mercs, is mirrored in his unaccustomed back seat role. Former Ford and Mercedes rallyist, now better known for his Paris-Dakar exploits in Mitsubishi’s Pajero, Cowan has certainly not had this perspective on life at 150 mph before.

Neither have the other occupants had to endure such consistent speed and provide conversation: Mercedes-Benz United Kingdom Public Relations manager Erik Johnson and Dipl-Ing Frank Knothe, one of Daimler Benz development engineering chiefs amongst the thousands employed at Unterturkheim, fall silent as the orange speedometer needle rests on 150 mph.

Al 145 mph indicated you can chat, at this 150 mph pace Millbrook’s yellow line to mark the preferred upper safety limit edges towards those 7J alloy wheels now bearing a load that must exceed the static two tons (car plus occupants) handsomely. Conversations are stilled as the clear analogue instrumentation that lies behind the massive four spoke steering wheel records further progress.

Now the speedometer flickers beyond 155 mph on the dial, the tachometer as unruffled at roughly 5250 rpm as the oil pressure and water temperature gauges. I complete two more laps at this indicated maximum pace. Drifting grey clouds, snatches of verdant Bedfordshire countryside and those omnipresent banking rails whipping by our cocoon of electronically managed steel and glass.

Conversation begins again as the S-class settles into the muted roar of sustained speed.  Everyone, even the previously impassive engineer, is relieved that the mystique of Mercedes has revealed another aspect of fast motoring: the 150 mph living room approach!

A later sortie in a LHD model, complete with a computer that is not yet available for RHD persuades Andrew Cowan to drive us over the twistiest and hilliest sections of this magnificent GM track. Andrew drives with calm and experienced speed whilst we experiment with the suspension settings available on this powerful saloon.

Initially we marvel at the automatic provision of firm and soft damper action provided by the prompting of a mercury switch, in turn activated by any increase in cornering speed (0.5G is the lateral threshold) and the manner in which it reverts to the original soft setting after four seconds of slow travel.

Complete with twin coil springs and gas pressurised dampers on each rear semi-trailing arm and wishbone front suspension, the largest Mercedes saloon swoops around our hilly terrain with impressive agility. The Japanese have promised such abilities before with “inflight” adjustable damping, but this system works and we are promised further development in cheaper models

Equipped with hydropneumatic suspension the 560s — and less powerful LWB models such as 420 and 500 SEL — feature variable ride height. We first encountered this on the prototype 190E 2.3/16s at Hockenheim, when it had been particularly useful for their three car record-braking runs at Nardo. Herr Knothe assures me that the mechanical principles are entirely different for the S-class, although it is true that elements of S-class self-levelling rear suspension did speed 2.3/16’s development of variable ride height.

However achieved, the object of lowering a car for high speed travel and raising for lower speed travel, is worthwhile. For an overall drop in height, together with a reduction in body to ground distances, contributes in the hunt for decreased air resistance with consequent speed and fuel consumption bonuses.

However, the biggest bonus to the driver, during that Millbrook exercise, was the appreciable increase in stability conferred as the system drops the 560 nearly one inch beyond 75 mph, only regaining that lost inch (0.94 inch for pedants) as speed drops beneath 68 mph.

Herr Knothe confirmed that the lower ride height creates that fashionable Formula 1 quality, “downforce”.  Meaning that the bodywork is actually loaded aerodynamically with consequent increase in cornering capabilities, provided such downforce is properly distributed!

This D-B engineering statement quite surprised me for I know of cases where manufacturers have mounted enormous rear wings and enlarged front spoilers without creating discernible saloon car downforce.

Conversation with chief development engineer Guido Moch is always a pleasure unless he is hurling you around the factory’s small and steeply banked test track, after lunch!  A ride in the equally capable 560 SEC left behind the knowledge that Daimler Benz not only holds its own brand of driver instruction courses, but also produces slick shod racing cars to enhance the instruction!

Currently BMW in Germany and Audi in the UK are making masterful noises about their respective brands of high speed driver instruction (I can recommend the BMW Rauno Aaltonen course, if  you can crack the enormous waiting list) but I gather D-Bs training is far more thorough.

Instead of an instructor being pleased with your progress once the inevitable marker cones are left intact, or a skid corrected, D-B times and measures all facets of your performance. Thus driver performances are accurately monitored: stopping distances, cornering speeds, all are relayed electronically.

The shame is that such factory-backed instruction is not offered to the public: members of Britain’s SAS force have benefited, along with other drivers who need counter-terrorist action, and there are successful graduates of D-B’s skill courses from Israelis to Arabs.

I asked Herr Moch, who has worked for D-B since 1959 graduation from the University of Karlsruhe, whether the slick-shod cars used for some speed instruction were simply European Championship Group A racers? “Oh no,” came the grinning reply, “we make all kinds of cars for this you know . . . big V8s with Formula 1 wheels and tyres. It’s fantastic fun, teaches us more about the car possibilities and the drivers can reach a higher standard.”

No, they did not want a journalist along on the course. Doubtless one of the “scoop” magazines will soon have a pic of the big-wheeled S-class and the caption (surely left set up from decade to decade?) “Mercedes make racing comeback!”

Trading as Mercedes Benz United Kingdom Limited (the parent factory’s Daimler-Benz dropped for obvious conflict reasons in the UK), the British end of a powerful and profitable Stuttgart giant — now busy diversifying into unrelated areas as well as building a third car factory complex at Rastatt — continued to set new sales records.

At first glance Benz commercial success in our country seems of much the same genre as has seen fellow townsmen Porsche clamber ever upward, prices apparently no bar to sales increases. For example Mercedes UK sold an extra 25, to set a new UK record of more than 18,000 cars in 1985. This year, despite the pound’s remorseless slide to a 3Dm exchange rate, the British operation is set to sell 19,500 units.

Of that near 20,000 annual sales rate some 7000 cars will be from the 190 range, one that the company says, “is important to us in making new friends, or what the marketing men call conquest sales.” That means Mercedes has been mildly surprised by the cross-section of machinery part-exchanged at its 105 British dealerships.

The obvious supposition is that the deadly rivalry between Mercedes 190 and BMW 3-series, one exemplified in saloon car racing by European Championship conflicts in 1986 and likely to be escalated by the 1987 arrival of M3, is also transmitted by trade-ins between the two marques. I understand this is not Mercedes experience in Britain.

One member of the Milton Keynes marketing force told me, “we actually get a lot of what we call aspirant cars in: Golf GTIs, Sierra 4x4s, that kind of thing, where the buyer is on the look-out for a car that says something more than mass production transportation.

“Of course we get 3-series, but I can honestly say it has been the variety of trade-in marques that has pleased us with the 190 range, which has also been made more freely available than any other Mercedes model. People in this category will not wait in the way traditional Mercedes buyers do . . .”

Mercedes is not likely to pursue BMW’s British sales boom. Munich’s representatives have been selling at an increasing volume ever since the factory took over the formerly TKM-owned concessionaires and 1985 saw them comfortably over 30,000 UK units. Just how long BMW can keep its upmarket posture whilst selling 3-series four cylinder models at Vauxhall/Ford prices remains to be seen. Mercedes-Benz in the UK wants none of it: “the plan is carefully restrained growth and we see 20,000 cars a year as a kind of threshold figure,” explained Erik Johnson. Like Porsche GB, Mr Johnson’s employers are concerned that too many cars will hurt resale values.

The 1986 sales season has seen Mercedes in Britain catch up on some of the established LHD offerings. These include the dramatically noisy air bag safety devices, revisions to S-class and SL models ranges, with repeated inline six cylinder and V8 capacity increases (2.8 to 3.0 litres for the sixes, 3.8 to 4.2, uprated 5-litres and now the 5.6 in V8s).  Britain has also received the middle-weight Mercedes Estates this year, an early priority because the UK is the best European market outside Germany for both estate and V8 Benzes.

The 190-related sales activity has reduced the average age of UK  D-B customers by five to ten years, but one gets the feeling they would still like a broader section of the sub-35 year old sector to opt for the tristar, and the signs are of effective action to support that ambition.

Next year’s introduction of the 2.6 litre six, a notably smooth fuel injection six normally found in 260E, into the 190 line (190E 2.6) promises to give Mercedes a more efficient challenge to BMW’s 325/320i sixes. Filling the Mercedes price chasm between £20,000 plus 2.3/16 and the £11,720 starting point of the 190 line.

I enjoyed driving Mercedes in such unusual company, but know I’ll not be joining the eleven GP drivers who have dealt with the factory’s travelling representative to acquire the latest in 560 motoring. However, I was puzzled as to why only Michele Alboreto and Nelson Piquet opted for the saloon.  Answers from the DSJ-AH combine in a plain brown envelope please. — J.W.