BMW Z4 sDrive28i review (2012 onwards)

Model: BMW Z4 sDrive28i
Bodystyle: two-door roadster
Engine: 2.0-litre turbo petrol
Transmission: eight-speed automatic
Date of test: September 2012

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What is it?

We should probably start by nailing down what it's not. BMW's Z4 sDrive28i is not a car with a 2.8-litre engine. Power comes from a 2.0-litre twin-turbo unit, an uprated 245hp version of the one that drives the entry-level 184hp Z4 sDrive20i.

No two ways about it, this roadster's name is misleading but we're getting used to that from BMW. As the hunt for ever-greater efficiency sees turbocharged powerplants creep increasingly into its range, the marque has taken to over-egging the badges on the boot. They're now best taken as a general reflection of the potency on offer rather than a measurement of the cubic capacity buyers get for their money.

On paper, there's no reason for anyone to feel short-changed anyway. Compared with the old Z4 sDrive30i, which really did have a 3.0-litre straight-six under the bonnet, this car is a shade down on power but it's quicker to 60mph thanks largely to a thumping 258lb ft of torque at 1,250rpm. It's a whole heap greener too.

Where does it fit?

The Z4 is BMW's current take on the classic roadster. It's a compact two-seat sports car with a convertible roof, the engine in the front and the power sent to the rear wheels. Coming from the brand that famously claims to build 'The Ultimate Driving Machine', it should be a lot of fun.

Rivals to this £35,000 roadster are not hard to identify. You've got the Mercedes-Benz SLK, higher-powered versions of Audi's TT and Nissan's 370Z. They're a talented bunch but the ever-present elephant in the room when discussing these cars is the mighty Porsche Boxster. It sits only a short hop up the pricing scale dangling its heritage and mid-engined handling purity in a bid to lure buyers away.

Is it for you?

Even in the face of this tough competition, the Z4 has a lot going for it. The latest models have proper drama in their styling with the tiny glasshouse perched at the back of a muscle-bound body full of bold, crisp creases.

When the hard-top roof's stowed, there's even more purpose about its looks. Your eye is drawn along the long, bulging bonnet to the stubby shark-like nose. It's aggressive rather than pretty and some angles work better than others but the Z4 appears to mean business from all of them.

The cheapest you'll pick up a Z4 sDrive28i for is around £33,500 but our car came with M Sport trim, the 8-speed Sport automatic gearbox, M Sport Adaptive suspension, the BMW Professional navigation package and quite a lot of other stuff besides. That took it sailing past the £45,000 mark.

What does it do well?

The twin-turbo engine in the Z4 sDrive28i is already replacing thirsty six-cylinder units in models across the BMW range and, for the most part, it does a fine job. The turbos work seamlessly together, adding prodigious extra muscle to the 2.0-litre direct injection, variable valve control unit while remaining all but undetectable from the driver's seat. Throttle response is sharp and there's no lag in the power delivery.

For the record, 0-62mph takes just 5.7s, a tenth quicker than the old six-cylinder sDrive30i could muster with its 258hp output, and that's largely thanks to the huge whack of torque on tap right across the rev range. It makes this Z4 effortlessly fast when you take it easy and seriously rapid when you fire up and down the 8-speed gearbox like you mean it. Do so and you're rewarded with the exhaust rasping on upcharges and popping as you lift off.

What doesn't it do well?

A good roadster should have a soundtrack that excites as much as its performance and that's one area where the four-cylinder Z4 sDrive28i can't quite match the old straight-six models. The engine sounds throaty enough accompanied by that loudmouth exhaust but as the needle sweeps up the rev counter the main thing you gain is volume. The sweet howl and subtle changes in tone that would tell you a larger, normally aspirated unit is working its pistons off are missing.

Handling wise, the Z4 is very capable with lots of grip and fine balance but the steering could definitely be sharper. You get a lot of information on what the rear wheels are up to through the driver's seat but the steering wheel is less communicative and its responses to inputs can seem fractionally delayed.

What's it like to live with?

The Z4 is only a small car; it would comfortably fit inside the footprint of the average family hatch, but because it sits you low down, towards the back of the chassis, and has you gazing out over an impressive bonnet bulge, it can be a handful to manoeuvre.

On the plus side, the ride is extremely well-judged. The optional adaptive suspension fitted to our car can crash over big scars in the road surface but otherwise, it smoothes the way expertly in Comfort mode and is far from harsh in the more focused Sport setting. It seems to be a big improvement over the standard M Sport springs, which can get a little jittery.

In the cabin, the Z4 is on the cosy side but you'd expect that in this kind of car. There's loads of headroom and enough adjustment in the driving position for a six-footer to get comfortable but the pedals are slightly offset. Build quality is largely excellent and the widescreen BMW Professional navigation system is one of the very best on the market.

The Z4's aluminium roof can now be retracted at speeds of up to 25mph and it operates in 20 seconds - quite quick considering the complicated two-piece design. With the roof down there's only 180 litres of space but leave it up and 310 litres is available. BMW claims it's enough for a set of golf clubs but the space is not uniformly shaped so you might have to melt them down first.

How green is it?

Despite what BMW tells you about the improved driving characteristics of the sDrive28i's 2.0-litre turbo engine we can be fairly certain that the real reason it's being offered is efficiency. Combined cycle economy of 41.5mpg and CO2 emissions of 159g/km make this BMW roadster something of an environmental star, when you consider the performance on offer.

Would we buy it?

The name might be confusing but if anything, the BMW Z4 sDrive28i itself is even harder to get a handle on. In M Sport guise it looks as aggressive and imposing as any roadster in the price bracket yet the driving experience isn't quite what you'd call razor sharp.

With the adaptive suspension and automatic transmission fitted to our model, comfort levels impressed more and that's despite the formidable pace of the 245hp 2.0-litre twin-turbo engine. When you factor in the slightly disappointing soundtrack, the plush cabin and the sensible economy, you're left with plenty of pros and cons.

In the end, much will depend on what you're looking for but we can confirm that it's great fun on a sunny day with the roof down and, when we're talking roadster, that's probably all that really matters.

First drive: BMW Z4
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