Alpina B4 Gran Coupe review: the thinking driver's BMW M4?

Hang on, what exactly is this car?

Well, given that BMW doesn’t make a full-fat M4 Gran Coupe, what you’re looking at is technically the pinnacle of the four-door 4 Series range. It’s the £79,900 (before options) Alpina B4 Gran Coupe.

What’s new about it?

Lots. The most powerful standard 4 GC is the 374bhp M440i xDrive, but Alpina uses its own specially modified example of the twin-turbo 3.0-litre straight-six S58 unit that’s found in the two-door M4. The tuner – which is now owned by BMW, as we’re sure you’re aware – fits smaller turbochargers that spool up at lower revs, as well as a new air intake, a new stainless steel exhaust and a performance cooling system. The result is 488bhp and a monstrous 538lb ft of torque.

Worth noting that makes the B4 GC more powerful than a standard, non-Competition spec M4 with its 480bhp, while giving it way more torque than the full fat M4 Competition which makes do with a measly 479lb ft.

It looks absolutely fantastic from behind.

Doesn’t it just? The classic 20-spoke Alpina wheels are now beautifully forged items and at 20-inches they fill the Gran Coupe’s arches nicely. Then again, nothing about the B4 is as aggressive as a full-fat M car: the rear bumper is new and gets muscular-looking vents, but the exhaust tips are a softer oval shape, the diffuser is super small and the lip spoiler complements that sloping roofline nicely. 

Shame about the front, though, isn’t it?

Ah yes, we knew we’d have to come on to this at some point. We’re still not used to the 4 Series’ grille, and perhaps if BMW wasn’t paying the bills then Alpina might have come up with a solution to its rabbit-toothed ugliness. As it is, you get a new Alpina front lip and a whole load of chrome up there. It’s not exactly subtle.

How does it drive, though?

It’s as accomplished as you’d expect. We’re already big fans of the M440i xDrive and even bigger fans of Alpina’s own B3 (which uses the same recipe and – after a recent update – gets the same power as this B4), so we weren’t expecting the Buchloe-based firm to mess this one up. 

The hefty torque figure helps it feel warp speed quick no matter what gear you’re in, with Alpina recalibrating the eight-speed auto to fit with the B4’s relaxed-but-rapid character. Changes are super smooth even in sport mode, with the driving experience accompanied by a muffled but purposeful soundtrack. Oh, and the quoted figures are 0-62mph in 3.7 seconds and a top speed of 187mph.

It’s comfort mode that the B4 defaults to though, and there’s even a ‘Comfort Plus’ setting to let you know that this is in no way an M car rival. Alpina fits what it calls ‘Sport Suspension’, but it’s never crashy and the damping is exceptionally-judged to allow for flat cornering and composed body control. 

It’s comfortable, then?

Everything about the B4 (and most Alpina products) is just supremely smooth. You get the sense that you should be on a German Autobahn where you could max it and still enjoy the crystal clear sounds of the Harmon Kardon stereo.

It’s not always the most engaging thing to drive on a UK B-road as a result even with a rear-biased 4WD system, but the speeds are intoxicating and traction is mighty. The uprated brakes are massively strong too.

What’s the interior like?

Our test car came trimmed in black leather which perhaps doesn’t show off Alpina’s interior talents to its greatest extent, but the classic green and black stitching is all present and correct. There are refreshed digital dials, although the new typeface isn’t altogether successful. Can you sense we’re nitpicking?

What else? Well, a slimmer steering wheel would have been a nice Alpina-esque option, but the larger aluminium wheel-mounted shift paddles are a really neat touch.

Would you buy one?

There’s no doubting the talents of the B4 Gran Coupe. It’s no less practical than the swoopy four-door it’s based on, and it pairs that with unrelenting pace and a premium-feeling interior. Its main problem though is that for £900 less you can start speccing a big-booted B3 Touring with exactly the same engine and chassis upgrades. And that car even has a normal-looking face. Tough sell for the B4, then.