A 6.9 may be better than a 69
Mercedes-Benz 450 SEL 6.9 (W116) – 1979
It may look just like the Mercedes-Benz 280 S that was made in numbers nearing the Beetle's, but there must be a reason why you could have bought two and a half 280s at the price of this 6.9 35 years ago.
You aren't showered with too many hints. The awkward, long Federal bumpers and the double headlights are there because this car was made for the USA. Eagle-eyed readers may notice that the rear doors are somewhat longer than the ones on a normal 116-Series Mercedes (the factory code of all S-Class Merc sedans between 1972 and 1979), but you could order even the rubber-band engined 280 version with an extended wheelbase and an “L” tag on its rear end.
The only clue is a “6.9” script at the right corner of the boot lid. Was it a European-spec car, you'd see a 450 SEL inscription at the left corner, too. But in fact, most of these cars had even the 6.9 badge missing right out from the factory. “De-scripting” had already been an option on this model and you can understand why.
This car has an engine with more cubic capacity than a medium-size fleet of vans added up. In fact it's the biggest Mercedes passenger car engine made after the war (not counting the AMG, Brabus and other specialist's versions). “Hubraum ist Hubraum” said zem Chermans reciting the American slogan happily. 6.9 litres of Stuttgart muscle divided to eight cylinders move this car along and that kind of opulence must have been a bit too much for a world struck by not one but two oil crises not long before the 6.9's debut in 1975. Hence the omission of the badge on most of the 7380 made of these brute limos.
If you look closer (and have read a thick bible on Mercedes-Benz passenger cars) you might indeed notice some features which are unique to the 6.9. There are the 215 wide wheels, the walnut birch insets on the dash (and practically everywhere)... And well, that's about it. The secret lies beneath the panels.
I forgot to mention one item though. It's a small knob on the dashboard, right below the instrument cluster. This is a feature only hydropneumatically suspended W116's got – and all 6.9's are like that. You got it, the way the system operates in the same what you'd have in bigger Citroens. In fact, Mercedes bought the whole lot that it installed in its top-end cars from the French.
The knob I'm talking about serves to raise or lower the car, just what the sliding lever does beside the handbrake of a Citroen CX. But Mercedes went a step further with the arrangement: the 6.9 rides not only on the hydropneumatic gas/oil spheres but it's also got huge supplementary rubber springs. If the system lets go, it sinks on these stoppers and would still be driveable. Of course it is better to avoid speed bumps in such a case.
I'd love to see the video footage when – learning from the vulnerable air suspension systems of the earlier W111, W100 and W109 models – Ze Board of Directors decided to buy the frowned upon hydropneumatics from the... erm... frowned upon Citroen. By God, what a victory may that have been for the French – champagne, Marseillaise and all that.
The 6.9 was a car of superlatives. “The world's fastest luxury sedan” and “the car that lists all technical innovations known in the business” – were some of the quotes cited in the brochures and even David E. Davis Jr. of
Car and Driver said it's “...the ultimate manifestation of the basic Daimler-Benz idea of how automobiles are supposed to be designed and built - the best Mercedes-Benz automobile ever sold”. And they weren't far from the truth.
If you just look at the numbers, it may not have seemed exceptional. There was the power: 286 PS for Europe, a measly 250 for the Americans. This makes a specific output of 41.4 PS/l for the old continent and just 36.2 PS/l for the US – not the thing anybody would have started a chat about at the pub even back then.
But a closer look reveals another number. That of torque. Here in Europe you got 549 Nm's of it, over the pond even emission-freak Californians got their 488 Nm's. That is certainly a lot today; it must have been unbelievable almost four decades ago. To stand that brute torque the 6.9 needed a special gearbox, so Mercedes ditched the fine four-speeder auto and installed a simpler three-speeder with gears almost double as wide as in the normal ‘box. To make sure that most of the power was transformed into moving the car a limited lip differential was also installed.
They went for certainty in the suspension department, too. Steel springs have a linear action when they are loaded but a hydropneumatic system progressively loads up and becomes stiffer as it is nearing the end of its travel. Thus a hydro-car – let me not write the whole thing down – is more suspect to leaning when it enters a corner. To counteract this, beefier anti-roll bars were used.
The layout of the suspension was otherwise the same as of the whole 116-range: pseudo-double wishbones up front, trailing A-arms at the rear – but in this car, the latter had been made of aluminium. Mercedes possibly created the most sophisticated suspension of the era; it was good in every aspect: comfort, road holding under different loads, and feedback. It could only be superseded when the five-arm rear suspension system came along – by the way, also devised by Daimler-Benz for the 190.
Lots of things were missing, however. You could order an in-car telephone (and later, even a fax) for 18,000 DM but that amounted to the price of two cheap cars in itself. And while the 116-series was the first car for which you could order an all electronic anti-lock brake system, extras that had been a must for already a decade then - like motorized seats and mirrors - were omitted from the options list. Even the doors were covered in shite-coloured, hideous synthetic leather.
The 6.9 in the movies
The 6.9 had a chief role in Ronin, a movie made in 1998. The film is full of staggering chases most of the cars used being Audi S8's, Citroen XM's and Peugeot 605's. The only odd vehicle in this quick-action movie set around Nizza is a European-spec 450 SEL 6.9 that Jean Reno drives in displeasingly amateur fashion, holding the steering wheel at just one point with both extended arms. Never drive fast like that; you'll fall off a cliff. Rumour has it that they used the old Merc in the movie because it was plausibly quick and it had a huge sunroof to stick the bazooka out of.
In David Lynch's Lost Highway the gangster boss Mr. Eddy (Dick Laurent) drives an American-spec black 6.9 that is said to have been tuned to 1400 PS. It isn't a car in good shape, it rides way too high but the chase scene is surreal anyways because Lynch used the cue button on the video player just a bit too much...
Funnily, the movie that has the closest ties with the 6.9 is one where you can't see the car at all. It is Claude Lelouche's C'était un rendez-vous from 1976. The whole movie lasts eight minutes. We're driving across Paris in the dusk at crazy speeds, there's not much traffic. The camera is mounted deep on the front bumper of the car. We're crossing junctions at red lights, hurtle along one-way streets at a ridiculous pace. To enhance the drama Lelouche dubbed the sound of a Ferrari 275 GTB on the film and it doesn't always match the action. Lelouche was cited to court because of the movie and he had to prove that most of the scenes were speeded up to avoid being convicted.
And it wasn't cheap either. In continental Europe you could have bought two Jaguar XJs from the 73,000 Deutsche Marks you paid for the 6.9 or you could have had the option of two Lincolns or Cadillac, too. Hey, you just needed to stretch a little further to buy a Rolls-Royce Silver Shadow!
Even compared to other Mercs it was eye-wateringly expensive. The nearest model to the 6.9, the plain 450 SEL – still with a beefy V8-motor – cost only 46,000 DM, the cheapest 116-series car, the 280 S, which looked almost identical to the 6.9, could be purchased for just 30,000 DM. The 6.9 was a blindingly bourgeois car in a time when small firms making petrol-guzzling specialist cars were going broke by the dozen, when fuel pumps were closing down by the thousands and even Arabian oil sheiks were thinking of downsizing their car fleets.
Peter Turoczy, who was a complete classic-car virgin didn't think that he would be in severe need of a car that needs a private filling station to go with it either - until 2011. Had he known that the light gold-coloured big Merc spotted on a chance visit at a collector in Budapest was said to be the most complicated car of its time, he'd probably have left it there altogether.
Spen King, BMC's chief engineer said of the 6.9 once: “if there is a way to make a car more complicated, Mercedes will find it.” But Peter hadn't the faintest idea how deep a pit he was jumping into. After all, 7000 Euros didn't seem like a lot of money for a completely rust-free huge classic Mercedes coming with leather seats, self-levelling suspension and a mighty V8 lump in its nose. He already had a hobby car at the time and guess what it is. A 124-series E500...
Peter persuaded a friend to join him in the business; they got the money together and took the car home that amazingly worked, although not too well. They only realised what they bought when they delved into Google. By then they couldn't take it back to the vendor.
Almost all stories start with the inevitable discovery of rust. And even more rust. And then some more rust, finally almost giving up the hope for resurrecting the whole piece of crap at the welder's. But this car had no corrosion at all, although it had been resprayed once. Its engine had never been dismantled. After a set of new brake pads the stopping system was perfect, at least that is what they thought. And the most important part, the small bits of trim; it was all there, chrome strips, wood, logos, the grille, the bumpers of the car, all original and intact.
But in every story with classic cars there comes a moment of truth, even if it's not the rust kicking up the bucket. And as many in the know say: the moment of truth is always more severe when you start resurrecting a car as complicated as a “Zechtskommaneun”, alias the 6.9. The engine was very hesitant in starting, it wanted to stall all the time, it was running on seven, six, sometimes five cylinders, there was some overheating and its consumption was soaring into 30 l/100 kms (7.8 mpg). Oh, the diff was also whining, the level-adjusting knob was dead and they could feel that the whole hydropneumatic system was grossly misbehaving.
There are rules of thumbs to keep when you're buying a classic car. One is: never lay your eyes on a complicated model that was produced in small numbers, because if it breaks (and it surely will do so), you'll never be able to get the parts for it. One supplement to this rule: if you find a donor to vandalise for parts, all the things you need will be missing, broken or worn to utter uselessness on the other car.
With that list of problems the Mercedes could have easily headed for donorship itself. But Peter is a nice chap, girls love nice chaps and Fortune is a goddess, which makes her... female. You have it, one smile flashed towards Peter from the deity and alas, there emerged a wreck from one of the eeriest back gardens of a small Hungarian house in the countryside. And it wasn't just any 116-series Mercedes, it was a 6.9. Considering the numbers it was made in, the whole story is becoming as improbable as hitting Mars accidentally with your kid's Nerf gun.
Fortune kept casting warm smiles upon Peter and his project. Although the newly found car was rotten almost beyond recognition, it was also crashed and vandalised, the rare differential, the special half-shafts, the level controller for the suspension – a worryingly sensitive device, that –, the housing for the thermostat (it broke while servicing the good car) were all in perfect condition. Phew.
From here it was just a case of installing the five new green spheres (Citroen-owners are probably familiar with these), the new hydraulic pump and the car was lifting itself. The structure of the seats had to be renewed but the leather upholstery stood to the ravages of time, heat and the sun surprisingly well. The engine received some new high-tension cables, plugs, relays and the injector nozzles went through a process of ultra-sonic cleaning. The nasty K-Jetronic injection system was tuned to perfection by András Árvay, long established pro of such devices and now the V8 is running like a Rolex.
I have to make a remark here: the key element to the longevity of a 6.9 is regular usage. Cars that are driven often seem to be indestructible and can cover zillions of miles but if they are stored too long, the fuel system, the electrics, the hydropneumatics all pack up soon.
By the time we got together with Peter to have a drive in his über-wagen, there were only small issues left. The tempomat still didn't work and the air-conditioning could only be set to maximum cooling, because the controls weren't working properly yet. By the way this space-age system had been devised and supplied by Chrysler for Mercedes in 1975 and when we're talking about the fragility of the complicated technical solutions of the 6.9, the suspension and this vie for the first place. As far as I know both problems mentioned above had found a remedy since the time of the testing.
I've driven a number of 116-series Mercs in my life before, most of them with the rubber-band 280 inline six, one with a 4.5-litre V8. They all seemed a bit, well, underpowered. But in this car all that mountain of torque just blows the laws of physics to dust. Even if you compare it to today's stronger cars a 6.9 is devastatingly agile.
And there's more. Its suspension is just as dream-like as a Citroen's but this one is good in corners too; you don't end up with your nose in the hedge if you mess up the turn. The funny thing is that it feels as if it were a smaller, more nimble than most Mercs.
With this sedan every sedate meter you drive is like strolling along the promenade in Nizza, even if you're just cruising along the suspicious living blocks at the edge of Budapest. Every time you bury the accelerator in the carpet, you set off a New Year's fiesta in carbohydrate world. When you're gentle with the car, the engine barely makes a whisper but when you unleash the power, you get that typical metallic German whine from the engine and there's a deep, faint shaking within the chassis not unlike of an ocean liner leaving the docks.
While all this noise-making takes place at the front, the rear end of the car squats to the ground alarmingly and that tennis court extending to the horizon before you suddenly vacuums up the road. And the small shiny thing at the end – it's not Agassi's head but the Mercedes star. It's a bit theatrical perhaps but as we know, all real luxury cars must have a mascot showing the way...
This isn't a barge, it's an ocean-liner on cocaine; it is deceptively quick in action but it always stays composed. A James Bond of a car it is; it can smother a dozen villains at a glimpse and only the knot of its tie gets loose in the process. Just a bit.
The driving was all done in Budapest but with so much excess power and that limited slip diff at the back it is really difficult to keep your head cool. So I didn't. There was the odd empty and wide intersection from the green lights before me, so I just kicked the loud pedal and prepared myself for the action. Oh yes, there's the Ronin-style drift, we covered three lanes in an angle that is for some reason is never illustrated in the pages of the book of Highway Code. This is hell! This is heaven!
Unbelievable car, this here. At one moment it is a whispering silk-bed of flowers devoid of all mechanical connections, then in the next it's a rubber-burning muscle car. The best of all is that is stays nimble when you press it on. The steering wheel may be huge like a taxi's but it turns only three from lock to lock so you have more control than you'd think when having some fun. Just to remember the taste of it, I indulged in a few more drifts before becoming a civilised person again. Sorry folks, you'd have done the same, and it wasn't my petrol...
Of course, being a hoodlum with a 6.9 needs a deep wallet. Now, as it is perfectly adjusted, Peter's car only asks for 17-18 litres of unleaded for every 100 kms (13-14 mpg) – when driven gently. The car has been ready now for almost two years so Peter already has had some experience with it. Once he tried to go for the top speed of 225 kph but lifted off the gas when the needle reached 220 – although the acceleration was still strong, it seemed to be a bit scary he said.
You might just want to know: the testers at Auto Motor und Sport measured the 6.9 with a fifth wheel when it was new and they could push it to 237 kph... Nonetheless Peter's car is the somewhat weaker American version and it also has a telefax in it, an original from the factory. Okay, I am lying, the actual machine still has to be found on eBay but all the special wires are there, because it was ordered for the car. Now that's a weight penalty too...
After an hour of riding the city's streets I hand the car back to the owner – surprisingly we still have fuel in the tank. I truly believed that the 116 is one of the best cars that had ever rolled off the production lines in Stuttgart, if somewhat underpowered. It is old enough to have a real car taste but it is modern enough to be comfortable and easy to drive. With the 6.9 you get that missing option – enough power. This silky beast just ate me for lunch, that's the truth. Imagine how I felt when I got back behind the wheel in my daily driver 1973 Mercedes after the test. It's a 220 D with 60 PS...
An oil-change interval of 20,000 kms in 1975
The 6.9-litre engine (derived from the earlier W109's 6.3) proved to be a bit too tall for the 116-series's low bonnet, so it was converted to dry-sump lubrication. It needed 16 litres of coolant; its oil pump circulated 12 litres of oil. There was a need for so much of the latter not only because the engine was huge but also because the valves had hydraulic tappets. When the engine wasn't running all this oil lived in a container integrated into the right front wing of the car (replacing the headlight was a nightmare), even the dipstick was stuck in this reservoir, so the level had to be checked at operational temperature.
All this oil, coolant, the nitrated valves, the hydraulic tappets, the bearing houses at the bottom of the engine block strengthened with an X-shaped brace racing car-style, the electronic ignition and the Bosch K-Jetronic mechanical injection meant that the maintenance need of the 6.9 engine was exceptionally low, it was probably due to tyre wear that the owner visited the garages the most often. Whilst cars of the time usually needed new oil and minor adjustments every 7500-10,000 kms, the 6.9 had to go to the service station at just 20,000 km intervals and only the oil had to be changed at these instances. There was a need for adjustments and checkups only after 80,000 kms which is a lot even today and was unheard of in its time.