Saturday, 2 August 2014

Alpina B4 Biturbo first drive Review | Autocar

Alpina B4 Biturbo first drive <b>Review</b> | Autocar


Alpina B4 Biturbo first drive <b>Review</b> | Autocar

Posted: 30 Jul 2014 02:15 AM PDT

What is it?

As next moves go, this was not hard to predict. Hot on the heels of the spectacularly well received D3 diesel saloon and estate, Alpina has now turned its attention to petrol-powered coupé and convertible versions of BMW's 3 and 4-series platform and this, the B4, is the result.

It costs almost exactly the same as an M4, produces almost as much power from a same capacity twin-turbo 3-litre BMW motor, and has a kerb weight within a couple of bags of sugar of an M4 (when also fitted with a paddle-shift transmission).

It also has a 0-62mph within a tenth of a second of an M4's, you'd be forgiven for wondering if the biggest difference between them is the letter that starts their names. But as with all things Alpina, the devil remains in the detail.

With its usual spectacular thoroughness, Alpina's 50 development engineers (a statistically negligible number to any normal manufacturer) have taken a 435i donor car and gone through its engine, gearbox, cooling system, wheels, tyres, aerodynamics, steering and suspension.

For a company making just 1500 cars a year, this is an extraordinary commitment.

Power from the N55 motor rises from 306bhp to 404bhp, thanks in the main to the replacement of its twin-scroll turbo with a pair of puffers, one either side of the engine and working in parallel. And while this is not quite so strong as the twin-turbo 431bhp S55 motor in the M4, its 442lb ft of torque is more than commensurately stronger than the 405lb ft offered by the M4.

It's kept the eight-speed ZF automatic transmission (disappointingly, and unlike the M4, no manual is available) but modified over 20 per cent of its components for faster, cleaner shifts.

On the chassis side, everything – springs, roll bars, dampers, bushes, bump stops – has been changed, but the overall strategy was to increase the springing medium by 40 per cent while allowing more damping compliance in bumps and less in rebounds.

Alpina's iconic 20-inch wheels, fitted with Michelin Pilot Sports developed specifically for the car, and vast Brembo brakes complete the picture. Note, however, that Alpina still does not provide a limited-slip differential as standard. It needs it less than a D3 but it still needs it and, at £1890, it is eye-wateringly expensive.

What is it like?

Expect a savage road warrior and you're going to be very disappointed by the Alpina B4.

Despite its menacing quad-pipe Akrapovic exhaust system, the engine starts quite softly and turbine smooth. The ride seems a little fussy at first until you realise you're hearing more than you're feeling.

Despite liquorice proportions, those sidewalls are actually 20 per cent softer than a standard Michelin of this size. If you leave the dampers in their default setting you can waft around all day in quiet and comfort. This has always been a key component of the Alpina proposition, and it's here again, front and centre.

Nail the throttle, though, and you'll find another side to its character altogether as in one silken wallop, it flings you up the road. The engine note is a smooth as a 1980s 2-litre six cylinder BMW, its thrust nibbling into junior supercar territory.

The gearbox is good enough to make you wonder why BMW insisted on a double-clutch transmission for the M4 and the overall performance package so strong yet civilised it could be a cage fighter with a first in fine art from Cambridge.

These standards are almost, but not quite matched by the chassis. The good news for skid scholars is that with the limited-slip differential in place, the B4 is beautifully balanced, nicer by far on and over the limit than the far more aggressive M4.

Perhaps more relevantly, ditching BMW's horridly squidgy wheel for a firm-rimmed replacement provides far better feel. The B4's weakness is in its damping which, for serious work, needs to have some of the bump dialled back in again.

This is a fine handling car and there was always going to be a price to pay for that secondary ride quality but there is just a touch too much body movement when travelling fast on difficult roads, a characteristic likely only to be exacerbated by anyone taking it to the track.

Should I buy one?

It's mightily tempting. The B4 over-delivers on the promise of both its looks and what we now expect from Alpina.

Its real skill is to provide a wider breadth of ability than any BMW using the same shell without contriving to be a jack-of-all-trades. It is damn near as fast as an M4, easier to drive, quieter and more comfortable – and while undoubtedly less exciting, ultimately no less satisfying at all.

If it is undone it is not by the M4 but its own, in house rival, the diesel-powered D3, a car certain shortly to be available in coupé, D4 form. What little the D3 loses in performance it more than recovers in torque, range and running costs, qualities than might make it less of a BMW but even more of an Alpina.

Alpina B4 Biturbo 

Price £58,950 0-62mph 4.2sec Top speed 188mph Economy 37.2mpg CO2 177g/km Kerbweight 1615kg Engine, 6 cyls, 2979cc, twin sequential turbos Power 404bhp at 5500-6250rpm Torque 442lb ft at 3000-4000rpm Gearbox 8-spd automatic

No comments:

Post a Comment