BMW’s new F10 5 Series may be closely associated with the 7 Series and 5 Series GT, but this doesn’t mean it’s simply a modified version of those cars.

‘In terms of driving dynamics, we always start from a clean sheet,’ explained Jos van As. But how, given the interrelation of components? By starting from the start, not working backwards.

Van As talks through the methodology, showing the 5 is more than a scaled down 7 (or, indeed, a 1/6th-price Rolls-Royce Ghost…). His work begins before a CAD pixel is created, through a logical build-up process:

•    DNA – ‘Here, we define proportions, weight distribution, drive concept, aero effects such as lift coefficient front and rear, and so on’
•    Suspension – Spring and damper rates are decided upon (‘ride quality was the focus with F10’)
•    Tyres – Design of car, weight of car under different load conditions (‘for example, we can decide what size wheels we can fit, and what pressures we need’)
•    Steering – Ratio, speed of response (‘the 5 Series has EPAS, like the 7 Series, but the ratio is faster’)

Once you have all this, you can begin setting up the standard suspension. With the 5 Series, says van As, ‘a team of 4 engineers set up the standard car.

‘This standard car is the base; we add on dynamic features to this platform, all controlled by ICM.’

As yet, then, there are no specific ‘sport’ suspensions for the 5 Series, but more dynamic variations of the standard car, created through technological add-ons. That’s what you can achieve with electronic dampers and adaptive anti-roll, ‘all controlled by ICM’.

Sounds like a cop-out? Not at all, such is the advanced level of ICM. ‘It’s all interconnected, all systems are parameticised. The chassis alone has 45,000 parameters – so it is quite hard work to get it right!’

Here’s where a strong, stiff body-in-white becomes vital, says van As. ‘It is important we get a good structure so we can discover how one change interacts with another.’

While those high-end cars could indeed have a fair few suspension settings, ‘the customer does not need 45,000 (!), so they get 4. ‘

‘These characterise the car in 4 different ways – making 4 cars in 1 from a dynamic point of view.’

Shrunken 7 Series, then? No – it’s a fair bit more than that…

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LAST year, I was sworn to secrecy. A fellow scribe and I nipped into BMW’s uber-secret FIZ development base, to have a swatch at the latest iDrive system. Which was to be installed in the even-more-secret new 7.

Down in the dungeon-like lair (keeping us away from windows, you see…), the BMW engineers gave the background of their iDrive philosophy.

Now, with old iDrive, turning and prodding 4-leaf ‘Rose’ menu was fine for the turn of the century. But, today, it’s limited. BMW needed a fundamental overhaul of its controller system. As we now know, and was shown to me then, the solution it found is brilliant.

‘We’ve kept the 4-Rose menu as ‘direct’ buttons,’ said the engineers. ‘But, if you’re trained in iDrive, you don’t use the buttons. You do the whole interaction WITHOUT looking at the controller.’

That’s fine, we wagered, but isn’t it even easier to have touchscreen? No, said a horrified engineer. See, touchscreen is absolute: ‘you need to guide your finger all the time, by looking at the screen.’ Imagine, they said, driving along and trying to input a nav destination.

‘iDrive is relative, though – you can turn, wait, give your attention to the road, but still know where you were when your eyes flick back.

‘This is a system for driving. We’ve designed iDrive in general to consist evolutionary steps, so you can see where you came from. It doesn’t overload drivers. And is, we feel, far safer.’

It’s not an issue of justifying cost saving, either. ‘Touchscreen is cheaper. But we don’t go for cheap. We go for premium – like Audi, like Mercedes-Benz.’

As we’ve seen, now it’s been launched the left-to-right hierarchy structure is, indeed, very logical. Proving BMW wasn’t lying when it got us to wear jazzy ‘goggles, limiting our vision to flashes within periods of total blackout.

Intended to replicate eyes flicking between display and road, it was a key test in developing the system. ‘Our tests amazed us – there was little difference in input time between wearing goggles and not…’

Believe me, these guys live and breath iDrive and instrument panels. Geeks, like me: hence, at the end of the day, all my geeky questions. They loved ‘em…

•    Why orange dials? Because it’s BMW, and the best colour for legibility. The worst? Blue and red, apparently…
•    Why an oil temp dial in the new 7? Because BMW is about engines, and it shows the brand’s sporty outlook.
•    Why not Lexus-style black panel dash? Because you should be able to see the dial tubes when the car’s turned off. To show they’re ‘real’ hardware. Mechanical.
•    Why not go all-digital instruments? Never! What’s more, there should be no visual split between mechanical and digital displays. The development and integration here took BMW years…

The engineers also proudly told me the left dial ‘tube’ was for velocity, and the right for ‘info’. Mirrored by the buttons on the steering wheel. Mirrored on the dash layout. Great! There’s a dash masterplan.

Shame the logic didn’t make the conversion to right hand driver, though. Think about it: because, no, BMW hasn’t switched the steering wheel buttons for right-hookers…

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