How many of you contemporary performance Benz owners have heard of the M100 Series? It started in 1967 as an experiment when a 6.3 liter 300HP engine and suspension from the 600-series was shoehorned into the more compact W109 series sedan chassis. Mated to a 4-speed auto and a special rear axle with a 2.85:1 gear, it posted 5.7-6.3 second 0-60MPH and 14sec Standing quarter miles while posing as Grandpa's Sunday cruiser.
The 6.3 series was discontinued and then reappeared briefly in the 77-79 450 SEL6.9 (which due to "refinements" and a rear axle gearing change for higher top speed posts about 1 sec. slower in the 0-60 fig.s). Though most of the few remaining 6.3s are over 30 years old, they still occasionally emerge at MB events to hold their own against newer, more sophisticated, computer assisted, technologically-advanced Mercedes performance cars.
The fact that these cars are primarily stock,pre-AMG,and aged and are yet still viable competitors is a testament to the farsightedness and solid engineering that still continues at MB today.

I have a webpage to display my own 6.3 pictures 1970 300SEL6.3

Also, if anyone would like to learn more about the M100 Series of Classic Mercedes Performers Mercedes Benz M100 EnginePerformance Series Cars