The 6.3 was first installed in the 600 Grand in 1963 -- all previous
Benz automotive engines were inlines -- the WWiI vintage "crowngear"
straight 8 in the German staff cars was supercharged -- above 3/4
throttle the blower was clutched in, went from 120 to 180 hp instantly.
No timing chain, the cam was driven by a set of 90 degree helical
gears.
Carb on that one, I think -- the mechanical FI was developed from
British patents shortly before WWII (a friend of ours father was the
original patent holder, in fact!) for the ME 109 inverted V12 aircraft
engine. It was adapted in the 50s, and first used in the 300 SL
"gullwing", I don't remember the engine number. Supplanted by D-jet in
1968, then by K-jet in 1976, followed by LH-Jet in the 90's, not
necessarily in that order (some engines used the older system while
newer designed used later systems in the same model line)..
Peter