It's easy to overlook the exact origin of the modern high-performance sedan. The concept first took the world by storm in the form of the marvelous 1968 Mercedes-Benz 300SEL 6.3, the birth of the modern "Q-ship."

It proved to the world that big, unassuming automobiles could secretively pack a lot of punch, breaking the stereotypical image of a performance car only coming in a compact package. It helped define the term, "sleeper." And it wouldn't have happened without the motivation of a "six-foot Bavarian hurricane" and once a leading engineer for the Silver Arrow, Erich Waxenberger.

Various media reported Mr. Waxenberger's recent passing at the age of 86. Being the 50th anniversary of Mercedes-AMG, the world-renowned luxury performance brand owes part of its spirit and startup to his legendary work.

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As an engineer, he was often regarded as a tour de force for Mercedes-Benz between 1956 and 1987. Known for pushing boundaries and prototype testers to the limits, often leading to their demise, insurance companies frequently pressured at-the-time CEO, Rudolf Uhlenhaut, to ban Waxenberger from driving. Uhlenhaut simply replied, "I'm just glad to have somebody who can push our cars to the limit. Leave him alone."

Erich Waxenberger is not only responsible for predicating the modern-day high-performance sedan. He also assisted Mercedes-Benz' rise in motorsports by collaborating with AMG Engine Production and Development, Ltd. The famed emergence of this team effort wouldn't have occurred without the 300SEL 6.3 serving as the main platform.

As his story goes, Waxenberger started working for Daimler-Benz's Passenger Car Testing division in 1953, following the immediate passing of his last exam as an engineering student. Birthed into a very automotive-centric family of DKW dealership owners, you can literally say he was born for the job.

In his earliest years, his first big project involved the development of the iconic W198 and W121 SL Roadster and Gullwings. By the 1960s, Waxenberger moved from road-testing prototypes to chassis development, beginning with the also iconic, "Pagoda" W113 SL Roadster. And this is where Waxenberger decided to get awesomely ambitious. He began secretively toying around with a lowly 230SL by taking the recently developed and famous 6.3L M100 V-8 engine originally commissioned for the aristocratic 600 limousines, and shoehorning it into the 230SL just to see if it could be done.

Tired of German automotive press deploring Mercedes-Benz' efforts of concentrating on boring, executive sedans, or "grandpa cars and taxis," Waxenberger did the unthinkable. With Mercedes-Benz pushing for lap time records on the Nurburgring Nordschleife, Waxenberger continued experimenting, leading him to come up the idea of taking the 6.3L M100 V-8 and stuffing it into the unassuming body of Paul Bracq's latest big-body four-door "SEL design" in 1966.

"The idea came from a German journalist who told me I was getting old, building Granny cars," Waxenberger told Classic Sport and Car in 1999, recounting his experience.

"I decided to show him and ordered up a SEL body rejected from Sindelfingen. We put the 6.3 V-8 into that. Uhlenhaut didn't know a thing about this until he heard it go past his office window late night and immediately insisted on driving the car. I wanted to get it right so I put him off for another day and we worked all night."

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Uhlenhaut, caught by surprise and intrigued, later drove the car and loved it so much, he took a prototype for an inter-continental sprint around Europe reportedly without trouble — impressive for when reliability was still an effort of much trial and head-scratching.

Two years later, the 300SEL 6.3 took its official bow at the Geneva Motor Show in 1968 after gaining approval from Mercedes-Benz. It further utilized the M100 engine production line capacity, helping its case. At the time, the 600 wasn't a rapid seller and reaching down market was necessary for Mercedes-Benz to optimize profits. But they did so with little compromise, selling a respectable 6,526 300SEL 6.3s worldwide.

Waxenberger's main priority during his tenure was to also race a car. The birth of the 300SEL 6.3 opened these doors for even more opportunity with automotive press often labeling it as the "greatest sedan in the world," completely shoving aside anything from Cadillac and Rolls-Royce. To prove his concept worked, Waxenberger took a 6.3 to the six-hour endurance race at Macao in 1969. The goal was to showcase his latest project's ability to withstand the brutal beating of an international rally course and win. He also mainly wanted to piss off the Porsche 911 crowd.

In succeeding test runs, he met up with a Mr. Hans Werner-Aufrecht after hearing about the establishment of AMG Motorenbau und Entwicklungsgesellschaft mbH in 1967. This is when and where Waxenberger and AMG began toying with the idea of increasing intake flow and the bore of the M100 to 6.8-liters. This roots the conception of the later famed 6.9-variant of the M100 for the 450SEL 6.9 (what was once the world's fastest production vehicle at the time).

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The peak of Waxenberger's career arguably led to the birth of the beloved motorsports variant of the 300SEL 6.3, dubbed the "Red Pig." Featuring that enlarged 6.8-liter AMG-prepped V-8, the Red Pig spearheaded Mercedes' newfound efforts in touring car racing at the time. In the late 1960s transitioning into the 1970s, European motorcar racing largely consisted of compact and nimble sports cars.

Against all odds, Waxenberger entered his latest collaboration with AMG and entered the 24-hour touring car endurance race at Spa-Francorchamps in 1971, taking second place behind a race-prepped Ford Capri. Part of the Red Pig's shock factor was that it was a giant land barge originally meant for transporting five passengers in intercity Autobahn sprints in the fastest, most comfortable, safest, and most reliable way possible — a complete polar opposite to the compact sports racer.

Despite its size, the Red Pig could hustle to 60 mph in nearly six seconds for a top speed of 142 mph — groundbreaking figures for the era. Furthermore, while many competing sports cars continued with endurance durability issues, with Mercedes-Benz and their impeccable engineering standards of that era, the Red Pig certainly gained attention from its reliability on the track.

Because Mercedes-Benz loved Waxenberger's concept with the 300SEL 6.3, they continued the idea with the next-generation S-Class in 1972 with the 450SEL 6.9 of 1975, a car I absolutely adore next to the 6.3 for simply how far ahead of their time both were.

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Following Waxenberger's peak with the 300SEL 6.3's success, he laid low to work on projects like the W123. But upon the launch of the third-generation SL with the R107 and C107, he reengaged his motorsports efforts. He later led the great rally exploits and success of the C107 AMG sports coupes (the famed 450SLC 5.0 AMG), particularly with the legendary 1978 South American rally, a grueling 30,000 kilometer (18,641 mile, yes you read that correctly) loop through ten countries, with an additional 3,728 miles of special stages, all over 40 days. The two top finishers were AMG-prepped C107 450SLC 5.0 coupes that he conceptualized and engineered.

Altogether, Erich Waxenberger's recognition might be overshadowed by other major key figures in Mercedes-Benz' and Mercedes-AMG's history. But his accomplishments and achievements are of no less value than any other great contributor to the automaker. So if you love and appreciate some of the finest automobiles to come from Mercedes-Benz or AMG, or even the idea of a performance luxury sedan sleeper, you can thank the ambitions of Mr. Waxenberger.