2020 Alpina B3 Sedan (G20) Dimensions, Size & Specs

The curb weight of the Alpina B3 Sedan (G20) is 1785 kilograms (3937 pounds). This reflects the car's weight with standard equipment including necessary fluids and a full tank of fuel, but without passengers or cargo. The maximum permissible weight, which includes passengers and cargo, is 2400 kilograms (5291 pounds). This weight balance provides the Alpina B3 with excellent handling and performance characteristics while offering the robustness and safety expected from a high-performance luxury sedan.

The Alpina B3 Sedan (G20) offers a luggage capacity of 480 liters (approximately 16.9 cubic feet). This is a competitive volume within the luxury compact sedan category, providing ample space for travel bags, groceries, or everyday items. The trunk space balances practicality with sportiness, allowing owners to enjoy performance driving without sacrificing cargo-carrying capability typical of family or executive vehicles.

The Alpina B3 Sedan (G20) comes equipped with rims sized 9.5J x 19 inches for the front and 8.5J x 19 inches for the rear. The tire sizes complement these rims with 265/35 ZR19 for the front and 255/35 ZR19 for the rear. These staggered tire widths optimize grip and handling balance, contributing to improved traction, cornering stability, and overall performance. The low-profile, wide tires enhance road contact, supporting the car's sporty driving characteristics that Alpina is known for.

With its length of 4719 mm (185.8 inches), width of 2068 mm (81.4 inches), and height of 1440 mm (56.7 inches), the Alpina B3 Sedan (G20) fits comfortably into a standard residential garage, which typically measures around 2440 mm (96 inches) wide and 5180 mm (204 inches) deep. The width including mirrors is an important consideration, but given its body width, most standard garages can accommodate the vehicle without issues. The height is well within standard garage door heights, so owners should find it practical for everyday parking.

Compared to its predecessor, the Alpina B3 based on the F30 generation, the G20 B3 Sedan is slightly larger in all key dimensions. The G20 measures 4719 mm in length versus the F30’s approximately 4627 mm, offering increased legroom and cabin space. The width of 2068 mm is broader than the F30's roughly 1827 mm, enhancing road presence and interior shoulder room. Height remains similar, though subtle styling changes provide a sleeker appearance. Overall, the G20 generation offers a more spacious and modern vehicle while retaining the performance pedigree of Alpina's B3.

The Alpina B3 Sedan (G20) is generally larger in width compared to similar luxury compact sports sedans such as the Audi S4 and Mercedes-AMG C43. For example, the Audi S4 measures around 4729 mm in length and 1847 mm in width, while the B3's width of 2068 mm stands out significantly. This extra width provides a more commanding presence and additional interior space. Length is comparable, with the B3 slightly shorter or similar depending on the competitor. In height and luggage capacity, these rivals tend to be close, but the Alpina's focus on combining sporty performance with spacious comfort is evident in its size.

The wide stance of the Alpina B3 Sedan (G20), measuring 2068 mm (81.4 inches) in width, offers several distinct advantages. From a handling perspective, the wider track improves stability during high-speed cornering and reduces body roll, allowing the vehicle to maintain better grip under dynamic driving conditions. Internally, the increased width translates to more shoulder room, making the cabin feel less cramped and enhancing passenger comfort, especially for front and rear seat occupants. This width excels in balancing athletic performance with luxury comfort.

The Alpina B3 Sedan (G20) stands at a height of 1440 mm (56.7 inches). This relatively low height helps lower the vehicle's center of gravity, which positively impacts handling agility and driving stability. A lower profile reduces aerodynamic drag and wind resistance, improving fuel efficiency and high-speed stability. Additionally, the sleek height contributes to a sporty silhouette, enhancing the car’s visual appeal while ensuring it remains practical for urban and highway use.

The Alpina B3 Sedan (G20) has a maximum permissible weight of 2400 kilograms (5291 pounds). This figure includes the combined weight of the vehicle itself, passengers, cargo, and any additional equipment. Managing the maximum weight is crucial in maintaining optimal performance dynamics, including acceleration, braking, and cornering. Additionally, this threshold ensures the car complies with safety standards related to structural integrity and suspension durability. The balance between curb weight and permissible load is engineered for both exhilarating performance and everyday usability.