Initiated by Erich Waxenberger as an internal ‘spare-time’ project, the 300 SEL 6.3 was the first Mercedes of its kind. Waxenberger decided somewhere in 1966 to plant the huge M100 V8 engine of the Mercedes 600 into the much smaller 300 SE coupé. When development director Uhlenhaut agreed on this somewhat strange project, Mercedes though it would be better to introduce this engine into its 300 SEL model. They mounted a 4-speed automatic to the M100 and kept all the refinements and luxury of the regular SEL model. The car was launched at the 1968 Geneva Motor Show as the fastest limousine of the world. At that time a top speed of 229 KM/h was indeed spectacular, but the same as the already launched Maserati Quattroporte I and the Iso Fidia. However the 0-100 KM/h in 6.3 seconds was much faster than all these existing sport saloons. Mercedes produced the 300 SEL 6.3 until 1972. Apparantly Mercedes decided to go with the project because they wanted to make better use of the M100 engine production facilities. Well, mission accomplished, because it sold more than 6,500 units, compare to just 2,700 units of the 600.

Technical specification Mercedes 300 SEL 6.3:

After the somewhat unexpected success formula of mounting a huge engine into an S-Class with the Mercedes 300 SEL 6.3, Mercedes did the same exercise with the recently launched W116. However the launch of the big lumped car was posponed a while because of the raging oil crisis. In 1974 the ‘regular’ Mercedes 450 SEL was awarded Car of the Year and at the same time the 6.9 was launched at the Geneva Motor Show, delivery started in 1975. The 6.9 was the most innovative (first Mercedes with hydropneumatic self-levelling suspension system and first car ever to get ABS) and most expensive. It cost in 1976 almost 8 times the price of a basic Volkswagen Golf and lined up near the most prestigious cars such as Ferrari, Bentley and Rolls Royce. The top speed was claimed by Mercedes on 225 KM/h, but journalists testing the 6.9 reported top speeds of 241 KM/h. By production closing in 1980 Mercedes had managed to build and sell more than 7,000 units of this magnificent car, a real tour the force considering the crazy era it was sold in.

Technical specification Mercedes 450 SEL 6.9: