Tag Archives: hydropneumatic suspension

Mercedes-Benz W116SEL – 6.9 Class – a Performance Classic

1978 6.9 Mercedes W116 450 S

We here at GoMercedes.com welcome our newest car that will be given a thorough restoration by the team. It is a top luxury sedan with an ultra high performance engine.  It is a 1978 Mercedes-Benz limited-production 450 SEL 6.9.

This classic  provides a smooth ride with a self-leveling hydropneumatic suspension.  It is designed for long distance cruising in comfort with more than enough room for a chauffeur, and roomy backseat leg space.  It also has extraordinary performance output.  It can accelerate from 0 to 62 mph in 7.4 seconds.

450-mercedes-selMagazine Advertisement for the 1978 450 SEL



The 6.9 M-100 engine is the largest most powerful V8 the company offered at the time and is factory rated at 140 mph.  The 6,814-cc V8 engines were hand built and  each bench tested  for 265 minutes, 40 of which under full load.  The engine generates an enormous output of 286 hp (210 kW) at 4250/min and a maximum torque of 56 mkg at 3000/min, providing the car with top-notch sports-car performance.

This fine example of German engineering was meant for the most discriminating of customers in the luxury market. There were only 7,380 of these cars ever built.  It’s formidable engine and luxurious options made it a favorite for tycoons, industrialists, politicans, and celebrities.  In 1978 the it’s last year of production in 1979 it sold for 81,247 DM or $45,703.33 US dollars.  In today’s dollars that equals $167,378.12.

At this particular level of wealth, often a subtle approach is the preferred means of travel.  The car could be ordered with option 261, which meant omitting the displacement figure on the trunk lid. This is exactly the case with this GoMercedes.com car as the 6.9 designation is not on the back. Those not in the know would never be able to detect the power the formidable engine that sits under the hood.

The W116 automobiles were the first Mercedes-Benz models to be officially called S-Class, although earlier sedan models had already unofficially been designated with the letter ‘S’ – for Sonderklasse or “special class.” The 450 SEL 6.9 W-116 was built on it’s very own dedicated assembly line by Daimler-Benz in Stuttgard, Germany.
The 6.9 also was the first car to debut the anti-lock braking system (ABS) – a safety system  that we take for granted today.

Press review of the Mercedes-Benz 450 SEL 6.9Automobil Revue, Switzerland, May 15, 1975:

“It is highly gratifying to see that at a time like this, a car appears that offers the highest levels of motoring enjoyment to the connoisseur – at all speeds. The 6.9 bears witness not only to the confidence those responsible have in the future but also to their courage to stand up for their beliefs.”

Car, England, June 1975:
“A car of such speed and weight must have demonstrably good roadholding and handling, and this one is no disappointment in anything from a hairpin to a three-figure bend: the suspension soaks up the bumps, the transmission is wonderfully smooth and admirably easy to control (either by a sensitive accelerator foot or a hasty hand at the lever), and the steering is servo-assisted in a way that highlights the nearly neutral responses of the vehicle.

Auto, Motor Und Sport, Germany, no. 21/1975:
“In measurements carried out by auto motor und sport on this, the most powerful German sedan, we recorded acceleration from standstill to 100 km/h in 8.2 seconds and 28.8 seconds for one kilometer from a standing start. We also registered a top speed of 234 km/h. While these figures are highly remarkable in themselves, the way in which they are reached in the perfect interplay of engine and automatic transmission is even more astounding. Notwithstanding the car’s weight, the overwhelming power of its quiet and smooth engine generates the highest levels of comfort and motoring pleasure.”

Britain’s Classic & Sports Car  – April 1999:
Ranked the Mercedes-Benz 6.9 fourth on their list of the “world’s greatest saloons.”

Mercedes Enthusiast May 2004:
Ranked the 6.9 number fifteen on their all-time top twenty list of great Mercedes-Benz automobiles.

The car’s top speed was factory tested at 140 mph, and weighs in at a substantial 4,200 lbs for comfortable Auto Bahn cruising. For stability it features an impressive self-leveling hydropneumatic suspension. The special hydraulic fluid required by the system is stored in a tank inside the engine compartment. The system is completely self-adjusting, and also ride height can be altered by a dash-mounted push-pull knob under the speedometer.  It can raise the car an additional two inches (50 mm) for increased ground clearance.

1978 6.9 Mercedes W116 450 S

The impressive M100 power plant with 6.9 litre displacement (417 CID) was made from cast iron, a V8 configuration with single overhead camshafts. It used sodium-filled valves (the kind found in piston-driven aircraft) against hardened valve seats on each aluminium alloy cylinder head.

Brock Yates an automotive journalist tested a factory issued 6.9 driving at street level speeds averaging around 72 mph from Manhattan to the Road Atlanta grand prix race track in Georgia.  When he arrived at the grand prix race track he drove it for an additional 40 laps (just about 100 miles).  The journalist reported no problems at all except just a bit of dust on the bodywork from the Michelin radial street tires.  Also the magnetic CB antenna blew off at 130 miles per hour.