The Alpina B3 Sedan (G20) 3.0, producing 462 horsepower, represents a high-performance variant of the BMW 3 Series (G20) platform. Produced between 2019 and 2022, it occupies a niche position between the standard BMW M340i and the full-fledged BMW M3. Alpina, a Buchloe, Germany-based automotive engineering company, independently refines BMW vehicles, focusing on enhanced performance, luxury, and exclusivity. The B3 Sedan is designed to offer a more refined and usable performance experience than the track-focused M3, appealing to drivers seeking a blend of speed and comfort. This particular variant, equipped with the 3.0-liter bi-turbo inline-six engine and all-wheel drive paired with the Switch-Tronic eight-speed automatic transmission, is the flagship of the B3 Sedan range.
Technical Specifications
| Brand | Alpina |
| Model | B3 |
| Generation | B3 Sedan (G20) |
| Type (Engine) | 3.0 (462 Hp) Allrad Switch-Tronic |
| Start of production | 2019 |
| End of production | 2022 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Combined fuel consumption (WLTP) | 11.1 l/100 km (21.2 US mpg, 25.4 UK mpg, 9 km/l) |
| CO2 emissions (WLTP) | 252 g/km |
| Fuel consumption (economy) – urban | 13.2 l/100 km (17.8 US mpg, 21.4 UK mpg, 7.6 km/l) |
| Fuel consumption (economy) – extra urban | 7.9 l/100 km (29.8 US mpg, 35.8 UK mpg, 12.7 km/l) |
| Fuel consumption (economy) – combined | 9.8 l/100 km (24 US mpg, 28.8 UK mpg, 10.2 km/l) |
| CO2 emissions | 224 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 3.8 sec |
| Acceleration 0 – 62 mph | 3.8 sec |
| Acceleration 0 – 60 mph | 3.6 sec |
| Maximum speed | 303 km/h (188.28 mph) |
| Emission standard | Euro 6d-ISC-FCM |
| Weight-to-power ratio | 3.9 kg/Hp, 258.8 Hp/tonne |
| Weight-to-torque ratio | 2.6 kg/Nm, 392.2 Nm/tonne |
| Power | 462 Hp @ 5000-7000 rpm |
| Power per litre | 154.4 Hp/l |
| Torque | 700 Nm @ 3000-4250 rpm (516.29 lb.-ft. @ 3000-4250 rpm) |
| Engine layout | Front, Longitudinal |
| Engine displacement | 2993 cm3 (182.64 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 90 mm (3.54 in.) |
| Compression ratio | 9.3:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | BiTurbo, Intercooler |
| Kerb Weight | 1785 kg (3935.25 lbs.) |
| Max. weight | 2400 kg (5291.09 lbs.) |
| Max load | 615 kg (1355.84 lbs.) |
| Trunk (boot) space – minimum | 480 l (16.95 cu. ft.) |
| Fuel tank capacity | 59 l (15.59 US gal | 12.98 UK gal) |
| Permitted trailer load with brakes (12%) | 1800 kg (3968.32 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Length | 4719 mm (185.79 in.) |
| Width | 2068 mm (81.42 in.) |
| Height | 1440 mm (56.69 in.) |
| Wheelbase | 2851 mm (112.24 in.) |
| Front track | 1577 mm (62.09 in.) |
| Rear (Back) track | 1572 mm (61.89 in.) |
| Drive wheel | All wheel drive (4×4) |
| Number of gears and type of gearbox | 8 gears, automatic transmission Switch-Tronic |
| Front brakes | Ventilated discs, 395 mm |
| Rear brakes | Ventilated discs, 345 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | Front wheel tires: 255/35 ZR19 Rear wheel tires: 265/35 ZR19 |
| Wheel rims size | Front wheel rims: 8.5J x 19 Rear wheel rims: 9.5J x 19 |
Powertrain & Engine Architecture
At the heart of the B3 Sedan is Alpina’s version of the BMW S58 3.0-liter inline-six engine. While based on the BMW unit, Alpina extensively modifies it with bespoke pistons, connecting rods, and a cooling system. The engine utilizes two twin-scroll turbochargers with intercooling, delivering 462 horsepower and 700 Nm (516 lb-ft) of torque. Direct fuel injection ensures precise fuel delivery, and the engine’s valvetrain features BMW’s VANOS variable valve timing system for optimized performance across the rev range. The eight-speed Switch-Tronic automatic transmission is also heavily modified by Alpina, featuring a unique software calibration for quicker shifts and a more responsive feel. This transmission is designed to provide both smooth cruising and rapid acceleration. The all-wheel-drive system, BMW’s xDrive, is tuned by Alpina for a rear-biased torque distribution, enhancing driving dynamics.
Driving Characteristics
The B3 Sedan 3.0 offers a compelling driving experience. The 462 hp and 516 lb-ft of torque, combined with the all-wheel-drive system, result in a 0-60 mph time of around 3.6 seconds and a top speed of 188 mph. The Switch-Tronic transmission provides seamless gear changes, whether in automatic mode or when utilizing the steering wheel-mounted shift paddles. Compared to the standard BMW 3 Series or even the M340i, the B3 feels more refined and less overtly aggressive. The suspension is tuned for a balance between comfort and handling, providing a compliant ride on most road surfaces while still offering excellent body control during cornering. The rear-biased all-wheel-drive system contributes to a playful and engaging driving experience, allowing for controlled power slides when desired.
Equipment & Trim Levels
The Alpina B3 Sedan comes exceptionally well-equipped as standard. Interior features typically include Lavalina leather upholstery, Alpina-specific interior trim (often utilizing wood or carbon fiber), sport seats with adjustable bolstering, and a premium sound system. Standard technology includes a large infotainment screen with navigation, Apple CarPlay, and Android Auto compatibility, as well as a suite of driver-assistance systems such as adaptive cruise control, lane departure warning, and automatic emergency braking. Optional extras often include a panoramic sunroof, upgraded leather options, and a more powerful sound system. The B3 doesn’t offer a traditional trim level structure; instead, customers can personalize their vehicles with a wide range of options and bespoke customization through Alpina’s Individual program.
Chassis & Braking
The B3 Sedan utilizes a modified version of the BMW 3 Series chassis, with Alpina-tuned suspension components. The suspension features stiffer springs and dampers, along with thicker stabilizer bars, to improve handling and reduce body roll. The braking system consists of ventilated discs at all four corners, with larger front discs (395mm) compared to the standard 3 Series. Alpina also upgrades the brake calipers and pads for improved stopping power and fade resistance. The steering system is BMW’s electric power steering, calibrated by Alpina for a more direct and communicative feel.
Market Reception & Comparison
The Alpina B3 Sedan was generally well-received by automotive critics. It was praised for its blend of performance, luxury, and refinement. Reviewers noted that it offered a more comfortable and usable performance experience than the BMW M3, while still delivering impressive speed and handling. Fuel economy, while not a primary focus, was considered reasonable for a high-performance vehicle, averaging around 24 mpg in combined driving. Compared to the M340i, the B3 offered a significant performance upgrade, along with a more exclusive and luxurious interior. However, it also came with a higher price tag. Reliability was generally considered good, benefiting from Alpina’s meticulous engineering and quality control.
Legacy
The Alpina B3 Sedan (G20) represents a compelling alternative to the traditional high-performance sedans from BMW’s M division. Its unique blend of power, luxury, and refinement has earned it a loyal following among enthusiasts. On the used car market, these vehicles hold their value well, reflecting their exclusivity and desirability. The powertrain, based on the robust BMW S58 engine, is expected to be reliable with proper maintenance. The B3 Sedan’s legacy lies in its ability to deliver a truly special driving experience, offering a unique and rewarding alternative to the mainstream performance car options.
