Curbside Classic: 1977 Mercedes 450 SEL 6.9 – Plenty Of Power But None For The Seats

(first posted 3/30/2011)    The Mercedes 450 SEL 6.9 (just “6.9” in the US) is a pinnacle vehicle, of one sort or another. Writers gushed about it then. Writers gush about it now. Everyone holds it in revered esteem. It was the biggest, baddest, fastest sedan of its time, able to leap tall buildings in a single bound. It cost almost as much as a Rolls Royce. But in order to truly understand the 6.9, and how such a car came to be, one has to know this: it had manually adjusting front seats. If one can properly comprehend that contradiction, then one has truly understood the German folk soul that created it.

The W116 Mercedes, and the 6.9 in particular represent perhaps the peak of that that oft-used term of German arrogance. The W116 was a mighty big, wide and heavy barge to launch into the teeth of the energy crisis. Of course, it was developed just before it. But the W116’s similarity with GM’s arrogant launch of its 1971 barges cannot be overlooked. Germans don’t have an exclusive on that quality.

Except of course that the two cars couldn’t be more different, with the exception of the their power plants, in general terms, anyway. The 6.9 used an enlarged version of the M-100 engine developed for that truly all-time über-Mercedes, the 600. Which of course was also used in the 6.9’s direct predecessor, the W109 300SEL 6.3 (I’m still looking. Update: found one, need to write it up).

The M-100 engine had every possible technical über-feature known to Swabians at the time: hand-built, bench tested and run for 265 minutes, 40 of them at full load; sodium-filled valves, 12 quart-dry sump oiling system, piston rings made from unobtainium, etc… Somewhat curiously, it had a cast iron block.

In Euro-trim, the 417 CID (6814 cc) V8 made 286 hp. The US version, challenged by the EPA, made 250 hp (both net). Don’t ask why I’m stuck on this comparison, but that’s the same as the Olds 455 made in 1972.  In fact a Delta 88 from that (big) year weighed about the same as the 6.9. Except in a straight line (and gas consumption), any other attempts to compare the two would be futile. But the Olds did have power seats.

Brock Yates was given a 6.9 to drive from Manhattan to Road Atlanta, to there drive at full chat for 40 laps. It averaged a respectable 72 mph, and was none the worse for it. No wonder Car and Driver called it the Greatest Mercedes Ever.

Instead of power seats, MB poured its engineering efforts into its hydropneumatic suspension, a first for them. Similar to the Citroen system, it was of course more reliable, but it did include rubber suspension stops, just in case. Mercedes drivers couldn’t be caught with the dreaded Mark VIII droop.

Its rated top speed of 140 mph (225 kmh) was commonly breached, probably more readily with the spunkier Euro version (is that what Yates was given?). Ultimately, 250 hp will only push a 4200 lb brick shit house so fast. Certain laws of nature are immutable, even by German engineers.

Just like GM, Mercedes got slapped around a bit by the W116’s dimensions and thirst. It’s successor, the W126, was svelte in comparison, narrower, considerably lighter and significantly more aerodynamic. And there was no more big-block version. But there sure as hell were power seats.

For another fifteen years or so, Mercedes would still be at the plateau of their peak years. Around 1990 or so, is when the beginning of the long Benz slide began. Is it a coincidence that it coincides with the unification of Germany? Did Germans feel like they had accomplished a national goal, and could relax a bit?

I remember perfectly walking into the exquisite W.I. Simonson Mercedes store in Santa Monica, which had previously been a Packard dealership, and built for that purpose. It was 1977, and the first 6.9 had recently arrived.

Let’s just say I wasn’t quite as well received and indulged as I had been as a kid at Iowa City’s GM dealer. Perhaps I was too young to notice or care back then. But the silver 6.9 sitting behind the left window there was locked, and the aloof and cool salesman eyeing me gave no indication of having it be anything otherwise.

For what it’s worth, the 6.9’s interior was really no big deal if you’s spent time in any W116. The only obvious difference was that burled walnut had replaced the plebeian striped zebrano wood. That pretty much goes for everything else about the 6.9, in terms of outward appearances. For almost double the price of a very adequate 450 SEL, the 6.9’s value was a bit of a stretch. I remember vividly looking at the $40+ k sticker, and having a hard time relating to it.

That price, inflation adjusted, comes to about $200k (in 2022), almost exactly what Daimler asks for one of its Mercedes-Maybach  sedans today. That does come with power seats, along with a slew of other conveniences. And I imagine a typical twenty-four year old would feel about the same inability to relate to its price.

The difference is whether twenty four year-olds even aspire to that kind of thing anymore. An impressive ride, undoubtedly, but utterly lacking in the German folk-soul that had us drooling over the 6.3 and 6.9 in its day. The long decline of Mercedes; and it all started when they put in power seats.