ALPINA D4 BITURBO REVIEW

List price from £50,950 Lease price from £858 The verdict 8

The Alpina D4 Biturbo is a rapid four-seater coupé that averages more than 50mpg

Is the best BMW 4-series actually an Alpina? This Bavarian company has been working with BMW for more than 40 years, making high performance versions of its cars that fit somewhere between regular BMWs and the range-topping M models. And the D4 Biturbo is a prime example.

It uses a modified version of BMW’s 3.0-litre diesel engine, tuned to produce more power and a load more torque. Plus the eight-speed automatic gearbox has been tweaked to suit the engine, and the suspension firmed up in an effort to improve handling.

Other upgrades include an Alpina exhaust system, Alpina alloy wheels and a bodykit designed to improve the aerodynamics and looks.

Space

Luxurious for two and acceptable for four

There’s lots of space up front, and while adults will feel a little cramped in the rear, the D4 still compares favourably with most coupés, being a genuine four-seater.

Similarly, the boot is on the large side for a car of this sort, with enough space for a suitcase and several smaller bags.

Rear seats that fold pretty much flat are available as an option. And up front, storage includes a useful lidded box between the front seats, a couple of deep cupholders, and door bins with bottle holders.

In addition to the coupé version that we tried, the D4 is available as a drop-top based on the BMW 4-series Convertible. This has a smaller boot, particularly when the roof is down.

Comfort

Very forgiving for a sporty car

While the sportier, M Sport versions of the BMW 4-series tend to jolt and jitter over bumps in the road, the Alpina D4 feels supple and beautifully controlled. True, it’s best if you stick with the standard 19-inch wheels instead of upgrading to the optional 20s, but either way it’s a surprisingly comfortable car.

The D4 also offers supportive seats, a good driving position and lots of adjustment, and while it’s engine note isn’t exactly inspiring, it’s perfectly pleasant. So the only thing that can make the car a little tiring on long drives is the road noise it generates over coarse surfaces.

Dashboard layout

Well-ordered dash looks and feels classy

Alpina offers some of its own interior finishes, but otherwise the dashboard is straight out of the BMW 4-series and none the worse for that.

You operate most functions by scrolling through logical onscreen menus using a rotary dial that’s positioned just behind the gearstick, where it’s easy to reach. And there are shortcut buttons that you can programme to take you straight to the functions you use most often.

The way the screen is positioned high on the dash is also welcome because it means you can always keep half an eye on the road. And everything feels solid and classy.

Easy to drive

Decent visibility and an excellent auto gearbox

Visibility is good by today’s (poor) standards, and rear parking sensors are standard, so you shouldn’t have too much trouble manoeuvring.

What’s more, the steering is usefully light at low speed and the standard automatic gearbox is one of the smoothest and smartest around.

Fun to drive

Brutal acceleration and agile in the bends

The Alpina D4 has a hugely powerful 3.0-litre diesel engine that can accelerate it to 60mph in about 4.5 seconds. But what’s more impressive is the near-instant response to you putting your foot down, and the way the engine’s immense thrust is available almost regardless of the speed you’re doing, making overtaking a doddle.

The D4 is also pretty enjoyable in the corners, changing direction eagerly and feeling taut and composed. However, as in the BMW 4-series, the steering lets the side down a bit; feedback is limited, so you don’t feel as involved in the experience as you might like.

Reliability

Warranty is disappointingly short

Alpina doesn’t sell enough cars to feature in any of the usual reliability surveys, but BMW has a decent record, which is encouraging given the D4’s origins.

More of a concern is the fact that Alpina’s warranty lasts for just just two years. Almost every major manufacturer gives you at least three years of cover these days, including BMW.

Fuel economy

Very good considering the performance

Despite accelerating almost as quickly as the BMW M4 performance car and having a higher top speed, the Alpina D4 averages 53.3mpg in official EU tests. And even in the real world, it will return more than 40mpg - about 20mpg more than the M4.

BMW’s 435d is a closer match for the Alpina, although it’s fractionally slower and not quite as frugal.

Affordability

Decent value, but likely to suffer heavy depreciation

The Alpina D4 is an expensive car, but its price doesn’t seem excessive when you consider the performance it brings, and thanks to the frugal engine, running costs are sensible.

Sadly, Alpinas don’t tend to hold their value very well; sell your D4 after three years ownership, and it will be worth less than half what you paid.

Safety

The essentials are there, but auto braking costs extra

The D4 hasn’t been crash tested by the safety experts at Euro NCAP, but the 3-series saloon to which it’s closely related achieved the maximum five-star rating, and every version comes with six airbags and electronic stability aids.

There are additional driver aids on the options list, including a system that warns you if a vehicle enters your blind spot, and another that automatically applies the brakes if it looks like you’re going to run into the vehicle in front in stop-start traffic.

Standard spec

Lots of luxury features, albeit with the odd omission

Alpina provides a long list of standard equipment, including climate control, a Bluetooth hands-free telephone connection, cruise control, xenon headlights, metallic paint and electrically adjustable leather seats, although it’s a little disappointing that satnav costs extra.

You can specify any of the optional extras that are available on the 4-series. And Alpina offers a huge range of its own personalisation options, including a hand-finished interior trimmed in the finest leathers and woods.