2014 Alpina B4 Cabrio Dimensions, Size & Specs

The curb weight of the Alpina B4 Cabrio is 1840 kg (4,056 lbs), which refers to the weight of the vehicle with all standard equipment, necessary operating consumables, and a full tank of fuel but without passengers or cargo. The maximum allowable weight for this model is 2300 kg (5,070 lbs), indicating the highest weight the vehicle can safely carry including passengers and cargo.

With the rear seats in the upright position, the Alpina B4 Cabrio offers a luggage capacity of 220 liters (7.8 cubic feet). When the rear seats are folded down, this capacity increases to 370 liters (13.1 cubic feet), enabling more flexibility for transporting larger items while maintaining the vehicle's cabriolet design.

The Alpina B4 Cabrio is fitted with rims sized 8J x 20 at the front and 9J x 20 at the rear, highlighting a staggered setup aimed at enhancing performance and aesthetics. It uses tire sizes 245/30 ZR20 for the front and 265/30 ZR20 for the rear wheels, which contribute to improved road grip, handling, and a sporty stance.

With a length of 4640 mm (182.7 inches), width of 1825 mm (71.9 inches), and height of 1380 mm (54.3 inches), the Alpina B4 Cabrio can fit comfortably in a standard garage, which typically accommodates vehicles up to approximately 5,000 mm (196.9 inches) in length and 2,400 mm (94.5 inches) in width. Thus, owners should not face issues maneuvering or parking it in conventional residential garages.

Compared to its predecessor, the Alpina B4 Cabrio maintains similar sporty dimensions but introduces subtle refinements for improved aerodynamics and interior space. While exact predecessor dimensions vary depending on earlier BMW 3 Series Cabriolet platforms, the B4 Cabrio typically offers a slight increase in length and width, enhancing cabin comfort and road presence, while keeping height and weight optimized for dynamic handling.

When compared with similar luxury cabriolets, such as the BMW M4 Convertible or Audi S5 Cabriolet, the Alpina B4 Cabrio generally falls within the same size range: around 4.6 meters (15 feet) in length and approximately 1.8 meters (6 feet) in width. Its luggage capacity is modest but competitive, prioritizing sporty dynamics and luxury over extensive cargo space. In terms of weight, at 1840 kg (4,056 lbs), it is slightly heavier due to its performance enhancements but offers a distinct blend of exclusivity and refinement.

The dimensions of the Alpina B4 Cabrio, including its length of 4640 mm (182.7 inches) and width of 1825 mm (71.9 inches), contribute to a low center of gravity and road-hugging stance essential for precise handling. Its relatively low height of 1380 mm (54.3 inches) lowers aerodynamic drag and reduces wind resistance, enhancing stability at higher speeds. The balanced weight distribution, influenced by its 1840 kg (4,056 lbs) curb weight, also complements agile cornering and a comfortable ride, making it a well-rounded performance cabriolet.

Yes, the Alpina B4 Cabrio balances performance and practicality effectively. While it emphasizes sportiness and luxury, its decent luggage capacity of 220 liters (7.8 cubic feet) expandable to 370 liters (13.1 cubic feet) with rear seats folded allows for everyday errands and weekend travel. The cabin space, influenced by its dimensions, supports comfortable seating for occupants without compromising the open-top driving experience, making it suitable for daily use and leisure driving alike.

Equipped with staggered 20-inch rims (8J front and 9J rear) and performance tires sized 245/30 ZR20 at the front and 265/30 ZR20 at the rear, the Alpina B4 Cabrio benefits from enhanced grip, stability, and cornering capabilities. These specific tire and rim dimensions allow the vehicle to maintain excellent traction during spirited driving, contributing to sharp steering response and reduced understeer. Additionally, the wide rear tires improve power delivery and stability, creating a confident driving experience inherent to Alpina’s performance ethos.