The 500 SL Mercedes-Benz
Fast, luxurious travel for two
Parting with the 500 SL Mercedes after a ten day holiday in North Wales was something of a wrench — in the 1,000 or so miles covered between walking in Snowdonia and inspecting medieval castles along the Welsh coast, the car almost became a way of life. Introduced at the Geneva show in March last year and arriving in the UK last summer, the 500 SL is the fastest car in the Mercedes range, and, apart from the Aston Martin Volante, is probably the fastest openable car in production. That is not to say that it is a wild, hairy sports car: it is not, being extremely docile and temperament free — which is what one expects from any car carrying the three pointed star. Mercedes quote a top speed of 140 m.p.h. and a 0-60 m.p.h. time of 7.8 seconds: I would not be surprised if the actual top speed was nearer 150 m.p.h. (with the hard top in place, of course) and my own 0-60 times averaged out at 7.3 secs. These figures and the price tag of just over £20,000 justify use of the epithet “super-car”. Mercedes themselves describe the 500SL as a “sports car”, presumably because it is an openable two-seater; but because it is not a chuckable, fiery mile-eater, I prefer simply to describe it as a luxury touring car for two — as such, it is wonderful.
To look at, the 500 SL is very little different from its immediate predecessor, the 450 SL, and is obviously a direct descendant of the 230 SL of the early 1960’s — Mercedes have this wonderful knack of making modern, new looking cars which appear very similar to the previous model and yet which do not make the older cars look dated. The changes which distinguish the 500 from the 450 SL are the additions of a small air dam under the front bumper soda spoiler across the boot lid, as well as the fitting as standard of the alloy road wheels which were optional equipment on the previous model.
The first thing which struck me as I walked around the car before taking it away from the Mercedes-Benz depot in Brentford was the quality of the paintwork. This particular 500 SL had been painted “petrol blue-green”, a most attractive colour which helped to emphasise the flawless, deep lustre finish which made the work of some high-class manufacturers’ paintshops look decidedly second rate. The pale grey leather upholstery, matching carpets and the simple veneer on the centre console all matched the quality of the exterior. When I gave the car a wash down before taking it for photography, I could not help noticing the substantial quality of all the exterior trim parts, and the care with which such items as the bumpers are blended into the overall design. Every exposed area of paintwork was easy to get at with a sponge and there were none of those very aggravating patches, usually very obvious, which attract dirt and which are impossible to get at without skinning knuckles on the back edges of bumpers or resorting to Heath Robinson cleaning devices.
The hardtop fitted to the 500 SL is substantial, well trimmed and fitted with a heated rear screen. The handbook recommends that it should be left to Mercedes dealers to remove this item for the period of the year when the soft top is in use, but it is a job which can easily be done by two men. Two handles are provided with the car which are used to unlock the two side mounting points, out behind the door pillars, and the two locking points on the windscreen upper rail. Concealed under the rear parcel shelf cum hood cover are the clamps for the rear of the coupe top which are controlled with levers fixed to the side of the luggage space behind the seats. This lever is also used for locking the hood frame in position. One has to remember to disconnect the electric cable feeding the heated rear screen.
Sadly, the period of the road test was extremely wet, rather cold, and there was nowhere to store the hard top in safety, so the car was only used with the hard top in place. The effect is to be driving a two seat coupe: there are none of the drawbacks or shortcomings common to hard tops, no rattles, drumming, excess wind-noise or leaks where it doesn’t quite fit. Sensibly, Mercedes have not been tempted to put a 1/4″ layer of upholstery over the area behind the seats for the sake of being able to call the car a 2 + 2, even though there would be more room for the passengers than in some so called four seaters, with the result that the interior of the car has plenty of room for two people and all sorts of oddments. This, together with the capacious boot (which has a rather uneven, carpeted, floor in order to accommodate the spare wheel), will satisfy those who change for dinner every day and could not possibly be seen wearing the same thing twice in a fortnight. The jack and a warning triangle are concealed behind a flap at the side of the boot, while a first aid kit sits prominently on the luggage shelf behind the driver’s seat. The handbook says that a fire extinguisher is positioned in front of this seat, under the drivers legs, but this item was missing from the test car.
The seats themselves are extremely comfortable, although lateral location for small people is somewhat inadequate when driving hard on twisty roads. Both seats are adjustable for position for and aft for rake, while the vertical position of the driver’s can be altered by relocating the guide rails. Safety head rests are fitted, and these can be adjusted through a wide range of positions to suit all shapes and sizes of people. It is possible to specify a seat heater as an optional extra. The steering wheel is of moulded plastic with a comfortable leather-grain type finish. The four spokes are set almost horizontally, and the large padded centre (containing, in a clear plastic insert, the famous three pointed star emblem) is the horn push. The steering column is not adjustable.
Through the upper segment of the wheel can be seen the three circular dials of the instrument panel. The central dial, larger than the other two, is the speedometer with the white-on-black figures reading in steps of five m.p.h. to a maximum of 170, and a back up scale in bronze figures shows the equivalent speed in k.p.h. The mileage recorder has six figures, and there is a trip recorder. To the right is the tachometer, reading to 7,000 r.p.m., but red lined at 6,000 r.p.m. Inset in the tachometer is a small diameter clock. The left hand instrument contains four quarter-dials. At the top, a fuel level gauge, which read empty long before the little arrow alongside it became illuminated to warn that there were less than three gallons left in the tank (which holds nearly 20 gallons when full). To the left, a water temperature gauge, reading in steps of 20C from 40 to 120C — normal temperature was just above 80C. Opposite this is an oil pressure gauge, calibrated in bars, reading up to 3. Normal Pressure during the test was about 2 1/2 bar, this dropping back to just over 2 bars at tickover with a hot engine.
The needle at the bottom of this left hand dial is labelled “Economy”. It is a rather sophisticated version of the vacuum gauges, or inlet manifold depression gauges as they are sometimes called, which the economically minded motorist has been fitting to his car for years. This one is not calibrated, but has an increasingly wide red band to indicate just how uneconomicaIly the car is being handled if the needle should stray into this area. Arranged in a horizontal strip below the instrument cluster are (from left to right) I.h. indicator warning light, charging system warning light, headlamp main beam warning light, handbrake warning light, the knob for resetting the trip meter, the variable intensity panel light switch, brake pad wear warning lamp and the r.h. indicator warning lamp.
To the right of the steering column are two stalks and, set in the dash, a rotating push-pull switch. The larger, lower stalk controls the indicators by vertical movement, the headlamp dipping and flashing by motion along the axis of the column, the windscreen washers by pressing the end of the knob towards the column and the windscreen wipers by rotating the knob into any one of the three operational positions — giving intermittent, medium and fast wiping. The headlamp wash-wipe operated automatically whenever the windscreen washers were used. Personally, I could not get used to this switch — it always seemed to turn in an unnatural direction, and yet when I thought about it and tried hard to remember which way it went, I was still wrong. In fact, the positions are clearly marked on the stalk, but this, for me, was always obscured by the steering wheel. The smaller stalk controls the cruise control — of which more later. The rotating switch on the dash controls the lighting functions, side or headlamps by rotation clockwise one or two positions, parking lamps by an anti-clockwise turn, front fog lamps by pulling the switch out one notch and those at the rear by withdrawing the switch to the second position. The ignition switch cum steering lock is to the left of the column.
At each edge of the dash is a swivelling ventilation outlet, each with its own control slide, which can be adjusted to blow warm air at just about any part of the anatomy. In the centre is a group of three such vents. with a single control slide, which feed fresh, non-heated air to the interior of the car. Immediately below this group are the switches for the heated rear window, and for the interior lamps (there are two sets of these, in fact, the footwell lights which illuminate only when the doors are open, and the windscreen rail lamp, operated by the switch).
The dash is linked to the transmission tunnel by a wood veneered centre console panel, at the top of which, immediately under the switches, is the stereo radio and cassette player, which is fitted as standard and is by Blaupunkt. The electric aerial operates automatically when the radio is turned on or off. The speakers for this are at the edges of the dash, below the swivelling vents. Below the radio is a panel containing the heater (or air conditioning, if this option is fitted) control slides, of which there are four controlling the direction and intensity of the warm air, together with the three-speed fan control switch and a dial to adjust the height of the headlamps to compensate for abnormal loading of the car. The heating system was extremely effective, and it was possible to vary the temperature across the car, so that my passenger, who has a strong dislike of heaters, could remain unheated, while I did not suffer in cold weather with only a light jersey for warmth. The doors are plumbed into the heating system, and warm air keeps the side windows clear. The wooden veneer extends back to surround the short, moulded plastic handled gear selector lever and the switches for the electric side windows and for the hazard flashers are set into this, just behind the lever. An ashtray, incorporating a cigar lighter, is positioned below the heater controls, just in front of the gear lever. The leather clad side members of the central console go right back between the seats, and form a useful oddments tray where the wooden veneer ends and the carpet starts. Capacity of this tray is limited by the handbrake lever which has only just over an inch clearance underneath it when in the off position. There are map pockets in each door, which one would have to remember to empty before using the car in the open state. and a lockable illuminated glove box which seemed rather small after the generous space elsewhere. The bonnet release catch is on the near side and there are well padded sun vizors which come away with the hard top.
A vacuum-operated master door locking system is employed, whereby locking or unlocking the driver’s door locks or unlocks the passenger door, boot lid and fuel filler flap. The passenger door and boot may be unlocked manually with the driver’s door locked, but this does not open the other locks. The driver’s door mirror is adjustable from within the car and there is no near side mirror fitted — it would have been useful in traffic.
Those are the luxurious appointments of this fine car. All worked as they were intended to, although, as already mentioned, I was not happy with the windscreen wiper switch (a personal quirk) — and I found the wipers themselves a trifle disconcerting at first. They are mounted very close to each other, offset towards the near side of the car. This means that the off side wiper has to cover a greater arc of screen than the nearside and the effect is the same as watching someone who is splay-eyed trying to cross his eyes. Nonetheless, they do work, and extremely well with no trace of lift at even very high speeds.
The rear hinged bonnet is self-supporting on a combination of strong springs and gas filled struts and is very thickly insulated. What it covers is a mass of wires, cables, tubes and machinery, all neatly laid out, and dominated by an enormous air cleaner. The engine of the 500 SL, as implied by the numerical designation, is of a nominal 5-litre capacity and is the same engine as employed in the 500 SE and SEL saloons, described briefly in Motor Sport in November last year. The V8 light alloy motor is a masterpiece of modern technology being extremely light for its size, having a very broad power range, excellent torque characteristics and being quite remarkably smooth. Designated the 117 engine, this is a unit which has been developed over the last few years to satisfy the Mercedes philosophy of trying to maintain or improve performance while reducing the quantity of natural resources consumed both in manufacture and use. This 5-litre engine gives the large S Class saloon the same performance as the previous 6.9-litre engine, and yet weighs a startling amount less. Considerable use has been made of some very special light alloys, and weight has been further saved by running specially treated pistons directly in the cast alloy block, doing away with steel or cast iron liners: in order to achieve this, the block undergoes an electro-chemical treatment which exposes silicon crystals in the surface of the bores, while the aluminium particles recede sufficiently for the piston rings to make contact only with the silicon crystals.
Single overhead camshafts on each head are chain driven and operate valves through hydraulically adjusted tappets. The bore and stroke are 96.5 x 85 mm. giving a total capacity of 4,973 c.c. and the power output is quoted as 240 b.h.p. at 9,950 r.p.m. Twin belts drive the viscous coupled fan, the water pump and the power steering pump and a separate belt is lined for the alternator. The battery is at the rear of the engine compartment, on the near side, balancing the huge brake servo in front of the driver. The washer water bottle is large, and positioned at the front where it is easily filled. The dip-stick is buried on the off side of the engine between exhaust pipes and is rather awkward to get out and put back. The electrics are Bosch, and the ignition system is transistorised and breakerless. The distributor is mounted high (something which pleased me on the flooded roads of N. Wales), at the front of the engine, and fuel is delivered to the cylinders by injection. The car consumed four-star fuel at the rate of 17.6 m.p.g. and did not appear to use any oil over 1,100 miles of very varied motoring.
This large engine started from cold instantly on every occasion, except one, when it had been lying unused for two days in the open, in heavy rain, which had cleared to a dewy evening and a frosty night: on this morning, I had to churn the engine over for what felt like an eternity before it started, but in fact it was less than a quarter of a minute. Once started, it settles down straight away to a steady tick-over of just less than 1,000 r.p.m., and pulls very well straight away. The temperature gauge comes up to the normal position, about 80°, quickly for such a large engine, and all is warm, even on a frosty morning, within two and a half miles of gentle driving.
The steering is power-assisted, and certainly needs to be. The 14″ alloy wheels are shod with 205/70 section tyres — in the case of the test car, Michelin XWX, and I discovered that the steering was amazingly heavy when trying to coast quietly at very slow speed into the car park in front of my flat very late at night. The tyres cope with the power and weight of the car (1,540 kg.) very well, even under conditions when I would have anticipated aquaplaning from much narrower section tyres. Despite the power assistance, the steering is positive and has an unobtrusive but pleasant live feel to it, the car responding well. The brakes are servo-assisted discs all round and very powerful. The pad area of the front brakes has been increased for this model, not so much as to improve performance but to increase life to help reduce servicing intervals. The pedal is light and progressive in action. The Mercedes anti skid braking system is available as an optional extra.
The transmission is through a new four-speed automatic gearbox. First gear only operates with the kick-down switch open, and is only really wanted for leaving black marks on the road, or for towing heavy trailers up the Alps. Second, the gear in which the car normally starts, whisks the car rapidly up to a maximum of 70 m.p.h., third goes on to nearly 120 m.p.h., while top is somewhat academic, but I can believe that it might approach 150 m.p.h., even though Mercedes quote a modest 140 m.p.h. maximum. The changes are imperceptible in normal driving, but somewhat sudden when backing off after a quick burst of acceleration to overtake. Delay on kickdown is noticeable, but not significant. The torque converter converts torque in a most impressive fashion, as I demonstrated to myself on a number of occasions by starting away from rest quite gently and increasing the revs to 2,000, then keeping the throttle such that this engine speed was maintained. It was interesting to watch the speedometer needle climb slowly round the dial until it reached the speed represented by 2,000 r.p.m. in top gear.
The ride is surprisingly soft, but not in any way sickly, although the car does roll noticeably on corners, despite the massive anti-roll bars. The independent rear suspension is of the trailing arm and coil spring type, while the front is by wishbones and coil springs, all very much as fitted to the 450 SL. Roadholding and handling were areas of the car’s character which I did not investigate to the full, being unable to take the car to a suitable testing ground. The car does stick to the road well and I found it difficult to unstick, even momentarily, except on damp or wet roads. The roll and the rather sensitive kick-down on the automatic box discouraged me from such antics, as I had the feeling that this particular model might be rather unforgiving in this respect. It was not intended for tail-out cornering, and I would not be happy to try it except in wide open spaces, with no-one else around! It is a fast luxury car for two, not a sports car.
Travelling by 500 SL is a lovely experience. On the motorways, the cruise control can be set to maintain the car at any speed above about 25 m.p.h. by flicking the control stalk upwards at the appropriate speed. If this is too fast, pressing the stalk downwards closes the throttle and the car slows down until the stalk is released, and the cruise control then maintains the slower speed. The control is switched off as soon as the brake pedal is touched, or can be manually released by pushing the stalk away. The set speed will be resumed if the lever is then pulled back. Motorway travelling on a lightly loaded road then simply becomes a matter of steering and keeping the eyes open. The interior is very quiet, with hardly any sound from the engine or transmission, a trace of exhaust noise if the car is being pushed, and no noticeable wind noise until the legal limit is approached. and then it is not obtrusive — it is only when high speeds are attained that the noise from the wind round the door mirror becomes annoying.
Driving the car through the Welsh countryside was a delight, the torquey engine making light work of any slopes or hills and being happy to pull from the lowest engine speeds in top gear on a light throttle, although the automatic change was very sensitive and would change down at the first hint of accelerator depression. The car was master of the open A roads, with the good all round visibility and the tremendous urge enabling we to pass other traffic with ease— the powerful brakes were invaluable for checking the speed of the car after a burst of hard acceleration to enable me to slot back into the stream of slower moving vehicles without inconveniencing anyone.
It was only when driving between Newtown and Llandrindod Wells that I was challenged. I had passed a man driving an elderly MG C between Welshpool and Newtown, and had noticed that he had speeded up to stick behind me, coming out of the stream of traffic to overtake whenever I did, and maintaining the same comfortable cruising speed some two hundred yards behind me when the road was clear. I could have used the Mercedes’ high top speed capability to lose him, but there was no point. However, coming out of Newtown, the road becomes extremely tortuous, and the MG was right on my tail. I could out-accelerate him between bends, but I couldn’t get away from him without being dangerous, the Mercedes rolling on the corners, and being very difficult to balance on the throttle unless high engine speeds were being held in one of the lower ratios, due to its inclination to change down suddenly. Compared with the Mercedes, the MG stayed flat, but hung its tail out from time to time.
But the Mercedes is not a sports car, and is not for boy racers — few could afford it, even if at £20,300 the car represents very good value, for the thing about a Mercedes is that it lasts a long time before any kind of tiredness sets in.