The BMW 8 Series M850i xDrive Steptronic, produced from 2018 to 2020, represents the initial offering in the revived 8 Series lineage (G15 generation). Positioned as the performance flagship within the coupe body style, it aimed to recapture the spirit of the original 8 Series while incorporating modern BMW engineering and luxury. This variant served as the primary launch model, showcasing the technological capabilities and dynamic potential of the G15 platform before the introduction of the M8 and other powertrain options. It was designed to compete with grand tourers from brands like Mercedes-Benz and Aston Martin, offering a blend of high performance, sophisticated technology, and luxurious appointments.
Technical Specifications
| Brand | BMW |
| Model | 8 Series |
| Generation | 8 Series (G15) |
| Type | M850i (530 Hp) xDrive Steptronic |
| Start of production | 2018 |
| End of production | 2020 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (combined) | 10.0-10.5 l/100 km (23.5 – 22.4 US mpg, 28.2 – 26.9 UK mpg, 10 – 9.5 km/l) |
| CO2 emissions | 228-240 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 3.7 sec |
| Acceleration 0 – 62 mph | 3.7 sec |
| Acceleration 0 – 60 mph | 3.5 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 3.6 kg/Hp, 280.4 Hp/tonne |
| Weight-to-torque ratio | 2.5 kg/Nm, 396.8 Nm/tonne |
| Power | 530 Hp @ 5500-6000 rpm |
| Power per litre | 120.6 Hp/l |
| Torque | 750 Nm @ 1800-4600 rpm (553.17 lb.-ft. @ 1800-4600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | N63B44D |
| Engine displacement | 4395 cm3 (268.2 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 89 mm (3.5 in.) |
| Piston Stroke | 88.3 mm (3.48 in.) |
| Compression ratio | 10.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Twin-power turbo, Intercooler |
| Engine oil capacity | 10.5 l (11.1 US qt | 9.24 UK qt) |
| Coolant | 10.5 l (11.1 US qt | 9.24 UK qt) |
| Kerb Weight | 1890 kg (4166.74 lbs.) |
| Max. weight | 2395 kg (5280.07 lbs.) |
| Max load | 505 kg (1113.33 lbs.) |
| Trunk (boot) space – minimum | 420 l (14.83 cu. ft.) |
| Fuel tank capacity | 68 l (17.96 US gal | 14.96 UK gal) |
| Max. roof load | 75 kg (165.35 lbs.) |
| Length | 4851 mm (190.98 in.) |
| Width | 1902 mm (74.88 in.) |
| Width including mirrors | 2137 mm (84.13 in.) |
| Height | 1346 mm (52.99 in.) |
| Wheelbase | 2822 mm (111.1 in.) |
| Front track | 1627 mm (64.06 in.) |
| Rear (Back) track | 1642 mm (64.65 in.) |
| Front overhang | 953 mm (37.52 in.) |
| Rear overhang | 1076 mm (42.36 in.) |
| Ride height (ground clearance) | 128 mm (5.04 in.) |
| Drag coefficient (Cd) | 0.33 |
| Minimum turning circle | 11.9 m (39.04 ft.) |
| Drivetrain Architecture | All wheel drive (4×4). Internal Combustion engine. |
| Number of gears and type of gearbox | 8 gears, automatic transmission Steptronic |
| 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 | Electric Steering |
| Tires size | 245/35 R20; 275/30 R20 |
| Wheel rims size | 8J x 20; 9J x 20 |
INTRODUCTION
The BMW M850i xDrive Steptronic, launched in 2018, marked the return of the 8 Series to BMW’s lineup after a nearly two-decade hiatus. Built on the G15 platform, which also underpins the 5 Series and 7 Series, the M850i was conceived as a luxurious and high-performance grand tourer. The “M” designation, while not a full-fledged M car, indicated a performance-oriented version of the 8 Series, boasting a powerful engine, sophisticated chassis technology, and a premium interior. The xDrive system denotes BMW’s all-wheel-drive configuration, providing enhanced traction and stability. This model served as the initial offering, setting the stage for subsequent 8 Series variants, including the M8 and convertible versions.
Powertrain & Engine Architecture
At the heart of the M850i lies the N63B44D 4.4-liter twin-turbocharged V8 engine. This engine is a significant evolution of BMW’s long-standing V8 tradition, featuring direct fuel injection, a valvetronic system for variable valve timing and lift, and twin scroll turbochargers. The engine produces 530 horsepower at 5,500-6,000 rpm and a substantial 750 Nm (553 lb-ft) of torque between 1,800 and 4,600 rpm. The engine’s architecture is longitudinal, meaning it’s mounted lengthwise in the chassis. The power is then channeled through an 8-speed Steptronic automatic transmission, known for its smooth and quick shifts. This transmission is programmed for both comfort and performance, offering manual shift control via steering wheel-mounted paddles. The xDrive all-wheel-drive system intelligently distributes power between the front and rear axles, optimizing traction in various driving conditions.
Driving Characteristics
The M850i delivers a driving experience that blends effortless power with refined comfort. The 4.4-liter V8 provides immediate and potent acceleration, with the car capable of reaching 0-60 mph in approximately 3.5 seconds. The 8-speed automatic transmission is well-matched to the engine’s characteristics, providing seamless gear changes and contributing to the car’s overall smoothness. The xDrive system enhances stability, particularly during cornering and acceleration on less-than-ideal surfaces. Compared to potential future M8 variants, the M850i prioritizes grand touring comfort over outright track performance. While it offers impressive handling, it’s tuned to provide a more compliant ride than the more aggressively-sprung M8. The steering is precise and well-weighted, providing good feedback to the driver.
Equipment & Trim Levels
The M850i came standard with a comprehensive array of luxury and technology features. Interior appointments included premium leather upholstery, multi-contour seats with massage function, a Bowers & Wilkins Diamond Surround Sound System, and a large 12.3-inch infotainment display with iDrive 7.0 operating system. Standard safety features included adaptive cruise control, lane departure warning, and automatic emergency braking. Optional extras included a head-up display, gesture control, and various interior trim options. The overall interior design emphasized a driver-focused layout with a luxurious and modern aesthetic.
Chassis & Braking
The M850i’s chassis is based on the G15 platform, featuring a double-wishbone front suspension and an independent multi-link rear suspension. Adaptive dampers were standard, allowing the driver to adjust the ride comfort based on driving preferences. The braking system consisted of ventilated discs on all four wheels, providing ample stopping power. The car also featured BMW’s Dynamic Stability Control (DSC) system, which helps to maintain stability during cornering and emergency maneuvers. The M850i’s suspension was tuned to provide a balance between comfort and handling, offering a more compliant ride than the more track-focused M8.
Market Reception & Comparison
The M850i was generally well-received by automotive critics, who praised its powerful engine, luxurious interior, and refined driving experience. Some reviewers noted that the car’s size and weight could make it feel less agile than some of its competitors. Compared to other trims in the 8 Series lineup (which expanded after the initial launch), the M850i represented the performance peak until the arrival of the M8. It offered a significant performance upgrade over the 840i models, while providing a more comfortable and luxurious experience than the track-focused M8. Fuel economy was typical for a high-performance grand tourer, with combined fuel consumption ranging from 10.0 to 10.5 l/100 km.
Legacy
The M850i xDrive Steptronic established the 8 Series as a credible competitor in the luxury grand touring segment. The N63B44D engine proved to be a reliable and potent powerplant, and the 8-speed Steptronic transmission has a strong reputation for durability. On the used car market, the M850i remains a desirable option for buyers seeking a blend of performance, luxury, and technology. While maintenance costs can be higher than those of more mainstream vehicles, the M850i’s build quality and engineering generally ensure long-term reliability, making it a compelling choice for enthusiasts and discerning drivers alike.
