6.3 Liters & 300 HP Make The 300SEL A Two-Ton Supercar
America may have invented the term “hot rodding”, but as a concept its appeal is universal, with no one nation rightfully able to claim itself the inventor—as long as there’s been motorized vehicles there’ve been power-hungry madmen looking to extract more oompf from their engines.
An all-time classic hot rodding example comes from Germany, as many of them do, this particular time in the form of Mercedes Benz’s legendary 300SEL 6.3. Widely regarded as the daddy of all mega-engined luxobarges, the 6.3 began life as the pet project of enterprising MB engineer Erich Waxenberger, who was blessed with the divine inspiration to shoehorn a 300 HP (SAE) M100 V8 from the 600 Grosser plutocratmobile into the relatively modest engine bay of the W109. The result was a nearly two-ton portable smoking room capable of 0-60 in 5.7 seconds—in 1966!
Rather surprisingly, a conservative Mercedes green-lighted the genteel monster and launched it at the 1968 Geneva Motor Show, ostensibly in order to better utilize production capability at the M100 engine plant, but perhaps more likely to show the world what MB engineering could achieve given the right mix of ingredients.
It certainly made an impression, easily capable as it was of cruising for extended periods of time at 200 km/h with five occupants cradled in luxury and safety—this at a time when the average family sedan struggled to achieve 100 MPH. Utilizing self-leveling air suspension, the 6.3 gave a remarkably smooth and quiet ride (perhaps only challenged by Citroen and their otherworldly DS—coincidentally Citroen’s olepneumatic suspension provided inspiration for a similar system employed in the 6.3’s predecessor, the mighty 450SEL 6.9) even for a luxury car, let alone one capable of performance greater than most contemporary exotic sports cars. Inside the lavish cabin, lucky occupants were treated with buttery leather, deeply polished wood veeners, chromed fittings, and dashboard architecture of a style and quality that can only be attributed to a more elegant and refined age.
The infamous AMG “Red Pig” finished 2nd at 1971’s Spa 24-Hour endurance race, an astonishing result for such a large and heavy car—it even featured an automatic transmission! Its engine was enlarged to 6.8 liters and made approximately 420 HP, and was reportedly capable of pushing the porky racer to 62 MPH (100 km/h) in just 4.2 seconds. It might have finished first were it not for its excessive thirst for fuel necessitating frequent pit stops, and its excessive weight necessitating frequent tire changes—there may indeed be no replacement for displacement, but there’s no cheating physics when it comes to the corners, either.
Replaced by the 450SEL 6.9 in 1975, both cars can be credited with paving the way for the type of supercar-baiting, 200 MPH+ übersedans and wagons that AMG (and indeed, M) now specialize in. The fact that performance has increased by only approximately 40% in nearly half a century speaks volumes as to how incredible the 6.3’s numbers were during their heyday—way back at the height of the Cold War, the Space Race, the Civil Rights Movement, and when the average computer took up several large rooms. What an achievement.