Bend it like Makinen

By DAVID LINKLATER

We're standing in the middle of a container port with a kilometre of clear tarmac in any direction. To the right, a fleet of discreetly signwritten cars. Left, a snaking course set out with orange traffic cones. Driver training? More like enthusiast education.

We're ensconced in this industrial corner of otherwise-spectacular Sardinia to experience the new BMW 5-series - and, in particular, a revolutionary piece of new technology.

Active Steering (AS) is a world-first variable-ratio system that will be standard on all New Zealand 5-series models from launch in October. BMW engineers claim that the development of AS is as significant as anti-lock braking.

It works like this: the Five's basic steering setup has three turns lock-to-lock. But AS can reduce that progressively down to 1.7 turns for low-speed work or tight corners, meaning that the driver seldom has to shift hand position on the wheel or even cross arms. It is ultra-responsive in delicate driving but still relaxed and stable at high speed.

It's not steer-by-wire. BMW says removing the physical connection between the steering and steered wheels would run counter to its driver-centred design philosophy. More importantly, it would be prohibitively complex and expensive - at least for now.

Instead, AS has an electromechanical adjuster between the steering wheel and steering transmission to add a positive or negative angle to the input from the driver.

When travelling slowly the adjuster works in the same direction as the driver, moving the front wheels further. At high speeds the adjuster works against the driver, making it less responsive.

Only in direct comparison with a non-AS car are you aware of the variable ratio system at work.

Otherwise it's unobtrusive and owners will quickly take it for granted that they can tackle hairpin corners with the grace (and fixed hand position) of a racing driver.

The AS is even networked with the car's Dynamic Stability Control (DSC) system to countersteer slightly at the onset of a skid. It's cutting-edge stuff. Along with a long list of other high-tech innovations, it's also proof that the Five is even more advanced than the avant garde 7-series.

Standard on all but the entry 525i is an adaptive bi-xenon headlight system that swivels with the steering to light the way around bends for safer night driving. It's not a new idea - the Citroen DS had it decades ago - but BMW's is more sophisticated.

Run-flat tyres are also included on all models, with extra-strong sidewalls that allow you to run with no air at 80km/h under full load for up to 150km (although BMW New Zealand will also supply a space-saver spare).

Slip inside and you find that the Five employs the much-criticised iDrive control system - but in a much simplified version. The controller moves in four directions compared with eight and it now features a menu button, which allows the user to return to the main screen at any time.

The Five's key is conventional and the gear-lever is located on the floor, between the front seats. Instrumentation is simple - sparse even.

There is one radical new feature for the driving environment - an optional "head up" display, which reflects selected information on to the windscreen in the driver's line of sight.

It's still under evaluation for New Zealand models, as its most useful application - satellite navigation - isn't in use here yet.

The 525i will provide an entry point to the New Zealand range, but the focus in Sardinia was on the 530 petrol and diesel versions.

The 170kW/300Nm 3-litre petrol engine is carried over from the previous model, while the 160kW/500Nm 3-turbo-diesel has been significantly upgraded, with 12 per cent more power and 22 per cent more torque than the previous car.

The petrol sixes will come with the choice of either six-speed manual or six-speed automatic gearboxes, while the diesel is a self-shifter only.

The 545i V8 automatic - with the new Valvetronic 4.4-litre V8 from the 7-series - will join the sixes next year.

The 530i petrol provides a musical soundtrack and searing acceleration of 0-100km/h in 6.9s, but it's the 530d turbo-diesel that's the star performer in the real world: the onslaught of peak torque from just 2000rpm makes it a stunningly quick point-to-point machine. It can rocket from 80 to 120km/h in 5.4s, compared with the petrol car's 7.3s.

The Five's chassis is as sharp as ever. It's larger than the present car - 66mm longer and 48mm wider - but is still 75kg lighter model-for-model thanks to aluminium construction from the A-pillar forward.

Suspension is derived from the 7-series and endows the Five with wonderfully fluent handling - especially with the optional Dynamic Drive, which employs active roll bars to eliminate 80 per cent of body roll during cornering.

Styling? Still controversial, the carefully crafted conflicting lines and wildly curved surfaces follow the family look established in the Seven and Z4 roadster, but the Five is less shocking and more elegant.

Significantly, the new car looks most striking in the metal, where the complex panel shapes play havoc with light and shade.

Pricing? The entry 525i and top 545i escape lightly with rises of $3000 each, to $94,900 and $162,900 respectively.

The 525i SE goes up $5000 to $102,900. Both 530 variants increase $7000 to $119,900 (diesel) and $120,900 (petrol).

The Steptronic automatic is a $4000 option on all but 530d and 545i, where it's standard.