The BMW 6 Series Convertible (E64) 650i Steptronic, produced from 2005 to 2007, represented the high-performance end of the E64 generation. Positioned as the flagship convertible within the 6 Series range, it offered a luxurious grand touring experience with a powerful V8 engine and a six-speed automatic transmission. The E64 itself was the first fully independent redesign of the 6 Series since the original E24, aiming to recapture the spirit of the classic coupe while incorporating modern technology and safety features. It shared its platform with the E63 6 Series Coupe and utilized BMW’s then-current design language, characterized by a long hood, short rear deck, and a driver-focused interior.
Technical Specifications
| Brand | BMW |
| Model | 6 Series |
| Generation | 6 Series Convertible (E64) |
| Type (Engine) | 650i (367 Hp) Steptronic |
| Start of production | 2005 |
| End of production | 2007 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (economy) – urban | 17.2 l/100 km (13.7 US mpg, 16.4 UK mpg, 5.8 km/l) |
| Fuel consumption (economy) – extra urban | 8.5 l/100 km (27.7 US mpg, 33.2 UK mpg, 11.8 km/l) |
| Fuel consumption (economy) – combined | 11.7 l/100 km (20.1 US mpg, 24.1 UK mpg, 8.5 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 5.8 sec |
| Acceleration 0 – 62 mph | 5.8 sec |
| Acceleration 0 – 60 mph | 5.5 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 4 |
| Weight-to-power ratio | 5.1 kg/Hp, 197.8 Hp/tonne |
| Weight-to-torque ratio | 3.8 kg/Nm, 264.2 Nm/tonne |
| Power | 367 Hp @ 6300 rpm |
| Power per litre | 76.5 Hp/l |
| Torque | 490 Nm @ 3400 rpm (361.41 lb.-ft. @ 3400 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | N62B48 |
| Engine displacement | 4799 cm3 (292.85 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 93 mm (3.66 in.) |
| Piston Stroke | 88.3 mm (3.48 in.) |
| Compression ratio | 10.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Engine oil capacity | 8 l (8.45 US qt | 7.04 UK qt) |
| Coolant | 14.2 l (15 US qt | 12.49 UK qt) |
| Kerb Weight | 1855 kg (4089.57 lbs.) |
| Max. weight | 2255 kg (4971.42 lbs.) |
| Max load | 400 kg (881.85 lbs.) |
| Trunk (boot) space – minimum | 300 l (10.59 cu. ft.) |
| Trunk (boot) space – maximum | 350 l (12.36 cu. ft.) |
| Fuel tank capacity | 70 l (18.49 US gal | 15.4 UK gal) |
| Length | 4820 mm (189.76 in.) |
| Width | 1855 mm (73.03 in.) |
| Height | 1373 mm (54.06 in.) |
| Wheelbase | 2780 mm (109.45 in.) |
| Front track | 1558 mm (61.34 in.) |
| Rear (Back) track | 1596 mm (62.83 in.) |
| Drag coefficient (Cd) | 0.31 |
| Minimum turning circle | 11.4 m (37.4 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Drive wheel | Rear wheel drive |
| Number of gears | 6 |
| Gearbox type | Automatic transmission |
| Front suspension | Independent, type McPherson with coil spring and anti-roll bar |
| Rear suspension | Coil spring |
| Front brakes | Disc |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | 245/45 R18 |
| Wheel rims size | 18 |
Powertrain & Engine Architecture
The heart of the 650i was the N62B48, a 4.8-liter naturally aspirated V8 engine. This engine was a significant departure from the inline-six engines traditionally favored by BMW. The N62 featured all-aluminum construction, double overhead camshafts (DOHC) with four valves per cylinder, and a relatively high 10.5:1 compression ratio. Fuel was delivered via a multi-port fuel injection system. The engine produced 367 horsepower at 6300 rpm and 490 Nm (361 lb-ft) of torque at 3400 rpm. The Steptronic transmission was a six-speed automatic, offering both fully automatic operation and a manual shift mode. This transmission was known for its smooth shifts and responsiveness, though it wasn’t as sporty as the available six-speed manual.
Driving Characteristics
The 650i Steptronic offered a refined and powerful driving experience. While not as overtly sporty as the 645ci with a manual transmission, the automatic provided effortless cruising and strong acceleration. The 0-60 mph sprint took approximately 5.5 seconds, and the car was electronically limited to a top speed of 155 mph. The automatic transmission’s gear ratios were tuned for a balance of performance and fuel economy. In everyday driving, the 650i felt composed and comfortable, with ample power for overtaking and merging. However, the weight of the car (approximately 4,090 lbs) was noticeable, especially during spirited driving. Compared to the 645ci, the 650i offered significantly more torque, resulting in stronger low-end and mid-range acceleration.
Equipment & Trim Levels
The 650i Steptronic came standard with a comprehensive list of features, including leather upholstery, power-adjustable heated seats, a premium sound system, automatic climate control, and a power-operated soft top. Optional extras included features like active steering, sport seats, upgraded leather trim, a navigation system, and adaptive cruise control. The interior design emphasized luxury and driver comfort, with a focus on high-quality materials and a clean, uncluttered layout. The standard dashboard configuration featured wood trim and metallic accents.
Chassis & Braking
The E64 650i utilized an independent suspension system, with McPherson struts at the front and a multi-link setup at the rear. This suspension provided a comfortable ride while maintaining good handling characteristics. The car was equipped with disc brakes on all four wheels, along with ABS (Anti-lock Braking System). The braking system was generally considered effective, providing ample stopping power. The 650i featured a hydraulic power steering system, offering precise and responsive steering feel.
Market Reception & Comparison
The 650i was generally well-received by automotive critics, who praised its powerful engine, luxurious interior, and comfortable ride. However, some critics noted the car’s weight and its relatively high price. Compared to the 645ci, the 650i offered a more refined and powerful driving experience, but it also came with a higher price tag and slightly lower fuel economy. The 650i’s fuel economy was rated at around 20 mpg combined, which was typical for a V8-powered luxury car of that era. Reliability was generally good, although some owners reported issues with the cooling system and the electronic components.
Legacy
The BMW 650i (E64) remains a desirable grand tourer in the used car market. The N62 V8 engine, while known for some potential cooling system issues (often related to the water pump), is generally considered a robust and reliable powerplant when properly maintained. The Steptronic automatic transmission has also proven to be durable. Today, these cars offer a compelling combination of performance, luxury, and style at a relatively affordable price point. The E64 650i represents a significant chapter in BMW’s history, showcasing the brand’s commitment to building high-performance, luxurious automobiles.
