Alpina B4 S Bi-Turbo 2018 Review

Sibling rivalry

The biggest challenge in getting the new Alpina B4 S off the ground in Australia won't come from Mercedes-Benz and Audi, but from the car it is loosely based on, a BMW.

With the price of a BMW M4 - unwittingly or not, the Alpina's most obvious rival - at historic lows, the fettled Alpina offshoot could have a hard task in appealing to buyers in bulk numbers.

The new B4 S starts at $149,900 (plus on-road costs) in Australia. By way of comparison, you can now pick up a BMW M4 Pure for $139,990 (plus ORCs), and a quick perusal of Carsales reveals low kilometre dealer demo models for some $20,000 less.

Alpina has never been one to appeal purely on value or price. Even so, the B4 S needs to make strong case on the road to strike a chord with buyers outside of reasons including badge cachet and nostalgia.

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The details

Alpina has held an unofficial relationship with BMW since 1965, essentially taking the Bavarian marque's donor cars, adding some discerning styling changes and, depending on your view point, luxury and flair.

In the case of the B4 S, Alpina has used the garden-variety 440i as a base. The matching B3 S borrows from the 340i.

Changes extend to 20-inch Alpina Classic alloy wheels, a new twin-turbo system, a stainless steel Akrapovic exhaust system with quad outlets, rear spoiler, Merino leather trim, electrically adjustable sports seats and front and rear parking sensors.

The new S model is physically identified over the 440i donor car thanks to a tweaked front and rear bumpers, new LED headlights and fog-lights and redesigned LED rear tail-lights.

Power is up, too, the B4 S' twin-turbo straight-six offering 324kW/660Nm and a corresponding 0-100km/h time of 4.2sec. The car's speed ceiling climbs to a supercar-bothering 306km/h, according to Alpina.

Meanwhile, adaptive Alpina sports suspension combines electronically adjustable dampers with springs, auxiliary springs and anti-roll bars, matched by a revised steering system.

In the skin

It won't take a train spotter to recognise some of the visual differences over the regular 4 Series.

The B4 S stands out on the road, whether it be via multi-spoke 20-inch wheels that cleverly disguise the valve behind the centre cap to clean up their appearance (the same as truck wheels do for safety), or the bespoke bumper designs, which are particularly prominent from the front.

There are also decals along the body which promise to divide opinion; they might be considered a bit "Fast and Furious", as one onlooker commented.

While the B4 S claims to break out with its own styling cues, it is unmistakably a BMW, employing the familiar Bavarian logos front and rear.

Inside, there are some more notable changes. Merino leather adorns the seats and contact points, including sections of quilted material on the door sleeves, while on our car, there are also lashings of woodgrain highlights.

The Alpina theme is strongly conveyed throughout the cabin, with at least a dozen instances of its logo across the steering wheel, dashboard, seats and door sills. Even the gauges in the driver instrument cluster bear the company's name.

There is also a plaque at the bottom of the centre fascia designating our test car's build number and stamp of approval.

Broad, comfortable chairs and a light, airy feel to the cabin underline a strong first impression upon settling into the driver's seat. The detail of workmanship is thorough, and the materials a genuine increase in quality over the donor car.

It all feels quite compelling, as though genuine effort has gone into upping the ambience of an otherwise tired 4 Series cabin now teetering on five years old. Others might simply find the makeover a tad gaudy.

The only real foible surrounds the car's paddle shifters. Alpina has eschewed the traditional flappy paddles for button-like controls on the back of either side of the steering wheel. They're difficult to use if we're honest.

Elsewhere, the B4 S' analogue gauges are showing their age, especially against 'new' BMW models including the X2 SUV, which trades it all for a swish digital set-up.
On the practical front, the B4 S eschews run-flat tyres for the real deal, plus an inflation kit. A two-year/unlimited-kilometre warranty applies, slightly off the pace of BMW's own in-house warranty and short of some other key rivals.

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On the road

In honesty, the B4 S feels more like a wicked-up BMW 440i than an all-out M4 fighter - which is good and bad.

First, the good: ride comfort. Alpina has thoroughly massaged the dampers, springs and bars to extract more comfort over bumps, a factor helped by the omission of the regular BMW's run-flat tyres.

Even on 20-inch wheels, the B4 S feels quite smooth on B-grade country roads as a result, transferring much of the pitter-patter stuff but soaking up larger hits, doing away completely with any thudding or jarring.

The car's steering is another sweet point, offering favourable levels of accuracy, feel and feedback irrespective of driving mode. We'd really love to try it back to back against an M4, but the initial suspicion is the B4 S felt the more organic of the two, particularly in sport mode, where the M-car tends to load up in weighting, almost artificially.

Withstanding that, the Alpina retains a sporty demeanour through the bends, though to this writer's mind, it doesn't quite capture the brash, bedded-down nature of the M4 - it's softer than that.

If anything, the Alpina feels more metered in its power delivery and cornering poise than the lightswitch-like M4, too; for many, this can only be a good thing.

While Alpina's changes make for a slightly more mature skillset on the road, engineers cannot completely disguise some common BMW 4 Series quirks; the biggest being road noise, which is a constant when on coarse-chip bitumen.

Then there's the engine. The on-paper stats read impressively - 324kW at 5500rpm and 660Nm at 3000rpm - and heady performance is clearly accessible when ambling around town. The engine is relaxed and generous in its power delivery, clinically cycling through the eight ratios on offer in a bid to match the 7.6L/100km fuel claim.

The initial response through the pedal can be tepid, but gently segues into a lush and accessible power curve and onwards to the most noticeable area of improvement - a fat, punchy mid-range. Progress is swift but never blinding, or certainly not as quick as Alpina's 4.2secnought to 100km/h claim from the seat of the pants.

The accompanying soundtrack is endearing though, our car making use of an Akrapovic exhaust system to bring a raspy but socially-acceptable note. And unlike the M4, it makes all of its sound organically, rather than through the interior speakers.

Verdict

The Alpina B4S does a genuinely good job of enhancing the standard 4 Series. It doesn't re-write the play book, and it cannot hide the donor car's inherent misgivings, but it applies a decidedly different flavour to the mainstream offering.

Whether the added expense over a 440i or even an M4 is worth the investment is another question altogether. It boils down to sort of character you're after in a BMW coupe: brash and wild or subtle and sophisticated?

Either way, at least with this version you're unlikely to ever spot another one in traffic.

2018 Alpina B4 S Bi-Turbo pricing and specifications:
Price: $149,900 (plus on-road costs)
Engine: 3.0-litre six-cylinder twin-turbo petrol
Output: 324kW/660Nm
Transmission: Eight-speed automatic
Fuel: 7.6L/100km (ADR Combined)
CO2: 177g/km (ADR Combined)
Safety Rating: Five-star ANCAP