1976 - The E24 6 series was introduced. It was available as 2 door coupe. There were two
           models available: the 630 CS and the 633 CSi. The 630 CS had a M30 6 cylinder
           engine with 185 HP. The 633 CSi also had a six cylinder but now with 200 HP.
1978 - BMW introduced the 635 CSi. This model also had a six cylinder but now with 218 HP
           and a top speed of 230 km/h. The 635 CSi had sport seats, alloy wheels, a front and
           a rear spoiler.
1979 - The 630 CS was replaced with a 628 CSi. It had a six cylinder engine with 184 HP.
1982 - The 6 series received a facelift. They now had a new dashboard and a service
           indicator. The 633 CSi went out of production.
1986 - The 628 CSi was no longer available. The 635 CSi now was available with or without
           catalist. The catalist version had 185 HP.
1987 - The catalist version received more power. It now had 211 HP.
1990 - The new 8 series was introduced in 1989 so the 6 series went out of production.

2005 - Should see the new e63 6 Series Coupe/Convertible.