The BMW 650i Convertible, part of the E64 facelift generation produced from 2007 to 2010, represented the performance pinnacle of the 6 Series range during its production run. Positioned as the flagship model, it offered a luxurious grand touring experience with a powerful V8 engine and sophisticated technology. The E64 facelift addressed criticisms of the original E63 generation, featuring revised styling, improved interior quality, and updated engine management systems. This variant, equipped with the N62B48B engine and a six-speed “Steptronic” automatic transmission, was aimed at buyers seeking a blend of performance, comfort, and open-air driving enjoyment in the premium large convertible segment.
Technical Specifications
| Brand | BMW |
| Model | 6 Series |
| Generation | 6 Series Convertible (E64, facelift 2007) |
| Type (Engine) | 650i (367 Hp) Steptronic |
| Start of production | 2007 |
| End of production | 2010 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 16.5 l/100 km (14.3 US mpg, 17.1 UK mpg, 6.1 km/l) |
| Fuel consumption (extra urban) | 7.7 l/100 km (30.5 US mpg, 36.7 UK mpg, 13 km/l) |
| Fuel consumption (combined) | 10.9 l/100 km (21.6 US mpg, 25.9 UK mpg, 9.2 km/l) |
| CO2 emissions | 258 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 5.6 sec |
| Acceleration 0 – 62 mph | 5.6 sec |
| Acceleration 0 – 60 mph | 5.3 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 4 |
| Weight-to-power ratio | 5.1 kg/Hp, 197.3 Hp/tonne |
| Weight-to-torque ratio | 3.8 kg/Nm, 263.4 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 | N62B48B |
| 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 |
| 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 | 1860 kg (4100.6 lbs.) |
| Max. weight | 2260 kg (4982.45 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 | 1374 mm (54.09 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 |
| Number of gears | 6 |
| Gearbox type | Automatic transmission |
| Front suspension | Double wishbone |
| Rear suspension | Independent multi-link suspension |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | 245/45 R18 96W RSC |
| Wheel rims size | 8 J x 18 |
Powertrain & Engine Architecture
The heart of the 650i was the N62B48B, a 4.8-liter naturally aspirated V8 engine. This engine featured all-aluminum construction, double-VANOS (variable valve timing for both intake and exhaust), and a Siemens MSV80 engine control unit. The multi-port fuel injection system delivered fuel directly to the intake ports, optimizing combustion efficiency. The engine produced 367 horsepower at 6300 rpm and 490 Nm (361 lb-ft) of torque at 3400 rpm. The six-speed “Steptronic” automatic transmission, a ZF 6HP26 unit, was specifically tuned to handle the V8’s power output. It offered both fully automatic operation and manual gear selection via steering wheel-mounted paddles or the gear selector. This transmission was known for its smooth shifts and responsiveness, contributing to a refined driving experience.
Driving Characteristics
The 650i Convertible with the automatic transmission delivered a distinctly grand touring experience. While not as overtly sporty as its six-cylinder siblings, the V8 provided effortless acceleration and a broad torque curve. The automatic transmission, while smooth, did add some weight and complexity compared to the available six-speed manual. The gear ratios were optimized for comfortable cruising, with a focus on maximizing torque in the mid-range. 0-60 mph times were consistently in the low 5-second range. The added weight of the automatic transmission and the V8 engine did impact handling slightly compared to lighter models, but the well-tuned suspension and precise steering maintained a composed and confident feel.
Equipment & Trim Levels
The 650i Convertible came standard with a high level of equipment, befitting its flagship status. Standard features included leather upholstery, power-adjustable heated seats, a premium sound system, automatic climate control, and a power-retractable hardtop. Optional extras were plentiful, including upgraded leather, active steering, sport seats, a head-up display, and various driver assistance systems. The interior design emphasized luxury and comfort, with high-quality materials and a driver-focused layout. The iDrive infotainment system, while innovative for its time, was often criticized for its complexity.
Chassis & Braking
The E64 6 Series Convertible utilized a robust chassis with a double wishbone front suspension and an independent multi-link rear suspension. This setup provided a good balance of ride comfort and handling precision. Ventilated disc brakes were standard on all four wheels, providing ample stopping power. The ABS (Anti-lock Braking System) and Dynamic Stability Control (DSC) were standard safety features. The 650i typically featured slightly thicker stabilizer bars compared to the 630i and 645i models to manage the increased weight and power.
Market Reception & Comparison
The 650i Convertible was generally well-received by automotive critics, who praised its powerful engine, luxurious interior, and refined driving experience. However, the high price tag and the complexity of the iDrive system were common criticisms. Compared to the 630i and 645i models, the 650i offered significantly more performance but came at a substantial price premium. Fuel economy was also considerably lower. The 650i competed with other luxury convertibles such as the Mercedes-Benz SL-Class and the Porsche 911 Cabriolet.
Legacy
The N62B48B engine, while generally reliable, is known to be susceptible to certain issues, including oil leaks and cooling system problems. Regular maintenance, including timely oil changes and coolant flushes, is crucial for long-term reliability. The six-speed Steptronic automatic transmission is also generally durable but requires proper servicing. Today, the E64 650i Convertible represents a relatively affordable entry point into the world of high-performance luxury convertibles. Well-maintained examples are sought after by enthusiasts who appreciate the combination of power, style, and open-air driving enjoyment. The car’s complex systems require a knowledgeable mechanic, but the rewards of ownership can be significant.
