Upgraded S58 engines now deliver 522 hp and a stack more torque than the facelifted M3 and M4
Through Chris Chilton
June 5, 2024 at 10:38 am
- Facelifted Alpina B3 and B4 renamed B3 GT and B4 GT
- The Alpina-tuned inline six-cylinder engine now delivers 522 hp, only 1 hp less than the facelifted M3 and M4, but with more torque
- B4 gets facelifted LED lighting from the 4-series Gran Coupé, B3 gets forged 20-inch wheels
Whenever BMW gives a car a facelift, you can be sure that Alpina won’t waste time upgrading its own versions of those same vehicles, and hot on the heels of the updated 3 and 4 Series sedans comes the new Alpina B3 and B4 GT.
The ‘GT’ tag is new, but it’s one that Alpina used last year for discontinued editions of the old 5 Series-based B5. In this case, however, the B3 and B4 GT are regular Alpina production models, although they do bring some significant changes compared to the regular B3 and B4 they replace.
Related: Is the BMW M3 Touring a better performance car than the Alpina B3 Touring?
One of those upgrades involves the S58 3.0-liter twin-turbocharged inline-six (same engine as the M3/M4), which gets a 34 PS (35 hp) power increase over the standard B3 and B4, bringing it to 522 hp. (529 hp / 389 kW). With Alpina now owned by BMW, it can’t be a coincidence that the parent company’s own 3 and 4 Series cars, the M3 and M4, are rated at 523 PS (530 hp / 390 kW) in their top-performing models. disguised after their recent midlife boost – 1 hp higher – retaining their status as top dogs.
However, the Alpinas produce more torque, producing the same 730 Nm (538 lb-ft) as before, and maintaining an edge over the BMW’s 479 lb-ft (650 Nm).
Those extra horses ensure that each of the three all-wheel drive GTs gets to 60 mph 0.2 seconds faster than the cars they replace. The B3 GT sedan now gets there in 3.4 seconds, a tenth faster than the M3 Competition xDrive, which takes the same 3.5 seconds as the B3 GT wagon and the B4 GT Gran Coupe.
Keep the pedal pressed and the lead over the old B-cars grows to as much as a full second by the time the new trio reaches 120mph, all gaining a few miles per hour at the top. The B3 GT sedan takes the win again, reaching a speed of 308 km/h, while the remaining pair reaches a speed of 305 km/h.
Chassis upgrades include a larger rear anti-roll bar and revised dampers on the B3s, and new dampers, reinforced front suspension mounts and a new steering tune and electronically controlled rear LSD on the B4.
All models now come with motorsport-style small canards and a front splitter, a new gloss black diffuser and black exhaust pipes at the rear. The B4 inherits the facelifted M4’s updated headlights and nifty 3D taillights originally seen on the M4 CSL, and the B3 now rolls on the 20-inch forged wheels previously reserved for the B4.