With so many engines to choose between, it’s easy for your brain to become boggled by the choices available. So allow us to try to simplify things a little. The first decision is whether to go petrol or diesel and that’s often as simple as knowing how many miles you’re going to cover in the car: the more you do, the more diesel makes sense.
If however it’s a petrol Astra you’re after – and leaving the VXR model out of the deliberations – the 138bhp 1.4-litre turbo is the best engine in the range, providing convincing performance (0-62mph in 9sec, top speed 126mph) with better fuel consumption than the gutless 113bhp normally aspirated 1.6-litre engine.
Vauxhall however appears to know this, so doesn’t make the engine available in any Astra below the quite ritzy SE grade. If you need a cheaper petrol engine, go for the 98bhp version of the standard 1.4-litre, which provides near identical performance to the 1.6, but vastly better fuel consumption.
But most customers will through choice or circumstance end up in a diesel Astra. The temptation here is to recommend that those looking for maximum fuel returns opt for the 1.3-litre motor while those looking for a long distance cruiser find the extra for the 2-litre.
However such an approach does not stand much scrutiny. For a start the 1.3 really is overwhelmed by the weight of the Astra and performance is as limited as its 93bhp output implies. But the killer is fuel consumption that actually worse than the most frugal version of the 128bhp 1.7-litre diesel which also offers performance of an entirely different dimension as their respective 0-62mph times suggest: 13.8sec versus 10.4sec.
As for the big 2-litre, like the 1.4 Turbo it’s not available below SE specification and while its performance offers a useful step up without a disastrous plunge in fuel consumption, it’s quite a noisy engine until you’re at a steady cruise.
For us then we think the 1.7-litre diesel provides the best cocktail of refinement, response and fuel efficiency so critical to success in this class.