2015 Vauxhall Astra 1.4 Turbo prototype first drive

More than a quarter of all British motorists have owned a Vauxhall Astra or have had one as a company car. Okay, you could probably say the same about a Ford Escort/Ford Focus, but it means the next version is a significant car for Vauxhall and one the company would like to get right.

That’s the reason, then, that this new Astra prototype, mostly developed in Germany by Opel, is being driven, disguised, around Bedfordshire. More Astras are sold in the UK than anywhere else and, according to GM Europe’s engineers, if a car’s chassis works here, it’ll work anywhere - at least, up to 60mph; for development above that speed you’ll want Germany. 

No Vauxhall or Opel, then, is signed off without beating the back lanes of Bedfordshire (which is near Vauxhall’s Luton HQ and its small facility within Millbrook Proving Ground) and Wales (which isn’t).

Currently, that Vauxhall is the 11th generation Astra, which we’ll drive in production form this autumn and which is a huge step-change over its predecessor. It sits on GM’s D2 architecture, which places lightness at the heart of everything.

The new Astra is 49mm shorter, 26mm lower and has a 23mm shorter wheelbase than the car it replaces. That helps make the new car at least 120kg lighter than its predecessor. Vauxhall says that’s a genuine like-for-like ‘at least’ claim, too. Fudge the maths, like some car makers, and you’ll find that a next-gen 1.6 diesel auto will be lighter than a current 2.0-litre of the same power by the order of 200kg.

How else has Vauxhall achieved that drastic reduction in weight? By using materials more smartly but improving manufacturing processes, and by optimising everything, everywhere.

For example, there’s no possibility of it being fitted with Vauxhall's advanced HiPer strut front suspension. The front suspension subframe is now attached to the chassis rigidly, rather than via bushes. There’s only room for a range of small engines. Manufacturing processes have been improved and parts on this car won’t have to double up on the next Zafira or other models.

In short, it’s less over-engineered than before. That the body-in-white is 21% lighter means that wheels, tyres and brakes are all now smaller, too. 

Despite the decrease in exterior size, Vauxhall reckons the new Astra's interior dimensions are up. I reckon so, too, after setting up a standard me-behind-my-driving-position test in the rear. With around four inches of spare kneeroom, and the same above my head, I’d estimate that only a Skoda Octavia matches it in the class.

In the front, things are as heavily disguised as they are on the outside. Covers are draped across all surfaces – even the instrument panel’s obscured from anything other than the driver’s seat – and peeking underneath, you’ll find fit and finish are pretty far removed from production. 

No matter, the driving position is okay, the gearshift action smooth and within 50 metres of setting off you can feel that this Astra – a 1.4 turbo petrol – is much lighter than the last one, an example of which Vauxhall has brought along for a back-to-back.