The B4 Gran Coupe is based on the BMW M440iX Gran Coupe with modified G80 M3 engine. It is the first model of the Alpina 4-series offered only as Gran Coupe model.

The B4 Gran Coupe replaces the Coupe version of the previous generation F32-based B4 S BiTurbo.

In March 2022, the B4 Gran Coupe was introduced.

The B4 engine is based on the BMW M3 engine, which has been modified to 495hp and 730Nm.

The only available gearbox is the 8-speed Sport-Automatic transmission (ZF 8HP76) with Switchtronic.

An electronically controlled limited slip differential is standard, ensuring a rear-wheel drive bias. The B4 features launch control from 0-200kph.

The B4 has adaptive sport suspension with electronically adjustable dampers, performance springs, bump stops and stabilisers. The suspension is modified with Alpina settings.

Wheels are 20-inch Alpina Classic with 255/35 and 285/30 Pirelli P Zero tires specifically developed by Pirelli for Alpina. The wheels are optionally available in black or anthracite.

The performance brake system features four-piston fixed brake calipers in blue with Alpina lettering and floating brake calipers at the rear. Brake disks are 395mm (front) and 345mm (rear). Optionally, high-performance drilled disks and high heat-resistant pads are available.

The B4 undergoes the same interior changes as usual with Alpina. Cluster gauges are custom Alpina with classic blue background combined with steering wheel trimmed in Lavalina leather. Additionally, interior trim is fine Alpina wood or piano lacquer with Alpina logos. A no-cost option are Alpina badges in the seats. Optionally, a custom interior in Lavalina leather can be ordered.

For the exterior, the changes are limited to an Alpina frontspoiler and Alpina badges on the rear. A non-cost option is the classic Alpina decor on sides of the car and frontspoiler. Available exterior colors include Alpina Blue and Alpina Green II.

Acceleration to 100kph is achieved in 3,7 seconds.
Topspeed is 301kph.