E24 6 Series (1977–1989)
The original 6 Series was the successor to the E9 coupés, namely the 2800CS, 3.0CS and 3.0CSi. The new E24 chassis was safer than that of the E9, meeting new United States federal crash and rollover standards. The original 6-Series was first launched in August 1976, with the 633CSi and 630 CS (not in US). This car had a 3210 cc engine with 197 PS (145 kW). In 1980 debuted the 635CSi, with a 3453 cc SOHC, 218 PS (160 kW) engine and a top speed of 222 km/h (138 mph). The 635CSi could reach 100 km/h (62 mph) in 7.4 seconds. A luxury version, known as the L6 arrived in 1987 with leather headliner and trim and other accoutrements.
The 630 CS used a 2986 cc I6 M30 engine with a Solex 4A1 carburetor, making 184 PS (135 kW) at 5800 rpm. The 633 CSi used a 3.2 L version of the same engine, but with a Bosch Motronic fuel injection system, which increased output to 200 hp (150 kW). The 630 CS was replaced in 1979 by the more affordable 628CSi, with a smaller displacement (2788 cc) but retaining the same power . It was fitted with the same Motronic fuel injection as the 633.
In 1983 BMW took the M88/3, a modified version of the M88/1 from the BMW M1 and put it in the E24 chassis, creating the M635CSi, or M6. This had a DOHC 24-valve 3453 cc, 286 PS (210 kW) engine, taken from the BMW M1 with a top speed of 255 km/h (158 mph). The M6 reached 100 km/h in 6.2 seconds. The M6 also had improved suspension, brakes, and a close-ratio manual transmission.
All were built in Dingolfing, Germany.
E63/E64 6 Series (2003–present)
An all-new 6-Series (E63) was introduced in 2003, filling the hole in the lineup left since the end of the 8-Series' production. Based on the underpinnings of the E60, the new 6-Series was introduced with a 4.4 L 325HP V8 engine for the 645Ci. In 2004, a more affordable inline six-cylinder engine was introduced in the 630i. This was soon followed by a convertible model (the E64), the first 6-Series with a removable top. Soon after its introduction, the 645Ci was replaced by the 650i, with a larger displacement (4.8 L) and 360HP. The range-topping M6 arrived in late 2005, using the same V10 engine as the M5, with 507 PS (373 kW).
- 2004-2005 645Ci - 4.4 L V8, 325 hp.
- 2004-2005 645Ci Convertible - 4.4 L V8, 325 hp.
- 2006- 650i - 4.8 L V8, 360 hp.
- 2006- 650i Convertible - 4.8 L V8, 360 hp.
- 2007- M6 - 5.0 L V10, 500 hp.
- 2007- M6 Convertible - 5.0 L V10, 500 hp.