Model review
Replacing the Z3 in 2003, BMW's Z4 is built to the same classic roadster formula as its predecessor. A selection of engines at the front of the car drive the rear wheels, while two occupants can enjoy open-top motoring.
The first cars were not given a particularly warm welcome, with somewhat divisive looks attributed to 'the Bangle effect', named for the influence of BMW's chief designer, Chris Bangle. However, the improvements over the Z3 in every other department saw it attract some praise.
A coupe version was also introduced in 2006, along with a mild facelift. BMW also included an 'M' model to top the range, with both Z4 M Roadster – a rare convertible M car - and Z4 M Coupe models available. Unusually, all version of this generation of Z4 were built in the USA, rather than Germany.
The Z4 was replaced with a second generation car in 2009, and this saw a move towards the fashionable retractable hard-top bodystyle, doing away with the need for separate convertible and coupe models. A facelift (BMW codenames these as 'life cycle impulse' – or LCI) was introduced in 2013.
There's no shortage of premium convertibles, so the Z4 always had its work cut out. The Mercedes-Benz SLC is the car largely credited with the popularity of the folding metal hard top from its previous SLK generation, while the Z4 is often mentioned in the same breath as the Audi TT and Porsche 718 Boxster. There's not much price overlap, but the Mazda MX-5 RF is a major rival too.
The Z4 is not long for this world, however. Production in Germany ended at the end of 2016 with a replacement, co-developed with Toyota and reportedly to be called the Z5, due in 2018.
Latest model
The latest – and probably last – version of the Z4 was the facelift model introduced in 2013. This refined the design of the coupe-cabriolet car with new headlight and tail-light designs and a minor reworking of the front end.
The Z4 is largely unrelated to any other BMW product mechanically. There are some major components from 3 Series models of years gone by, but it's very much a car apart from the range. Even compared to BMW's other current coupes – the 2 Series, 4 Series and 6 Series – the Z4 is clearly something a little bit different.
It's powered by a range of four and six-cylinder petrol engines, from the 2.0-litre, 154hp sDrive18i to a 335hp twin turbocharged sDrive35is. There is no longer an M model to cap the range, but the most powerful option won't have any trouble keeping up with any of BMW's other M cars.
Fuel economy varies from 31mpg up to 42mpg, which looks a little poor compared to modern Euro 6 compliant engines. All models are exclusively rear-wheel drive.
Although it's a relatively old car now, the interior is in keeping with current BMW models, with high quality materials and decent ergonomics. It's got a decent level of kit too, with BMW professional navigation as standard – usually a pricey option – and the brand's iDrive controller.
One thing to remember though is that this car has ceased production, so you won't be able to specify it precisely how you want.
Value for money
The Z4 certainly doesn't fall short of value for money on the purchase price – and with no new supply coming in, you may be able to bargain that down yet further.
Prices start at £30,010 for the sDrive18i model. This is kitted out with 17-inch alloy wheels, electric windows, drive performance control, manual air conditioning, Bluetooth, DAB radio, professional navigation and xenon headlights. It's only really the cloth seats that give anything away and that's replaced with leather on every single other model.
Prices top out at £48,465 for the sDrive35is model, which is a little on the steep side, especially as there's not a great deal by way of additional equipment to entice you.
It's the running costs that harm the Z4, really. The engine range, although badged as BMW TwinPower, only meets the older Euro 5 emissions regulations rather than the newer Euro 6 ones – part of the the reason the car was phased out before they came into force in September 2016.
The higher emissions means poorer fuel economy, with the best being 42mpg from the sDrive18i. The top model is particularly thirsty at 31mpg and you're not going to equal either in day-to-day driving. Insurance costs are high too, with the lowest insurance group being 34.
Residual values are harder to get a bead on now the car is effectively defunct. Certainly with the lower-powered models you're looking at a three-year retained value in the low 40% region and higher-powered cars, though more desirable, look a little old hat next to some of their rivals so could suffer more.
Looks and image
From what was once a much-derided car in terms of looks, the Z4 has evolved into one of the prettiest vehicles that BMW makes. It helps that it is visually different to the other coupes and convertibles in the range, differentiating it further.
It also has a stellar motorsports background. The Z4 has been campaigned in GT3 endurance racing across Europe until very recently – replaced by the M6 in 2016 – and has been remarkably successful too.
It's still a BMW though, and that comes with its own image. BMW owners are often tarred with a rather broad brush regarding their road manners and the aspirational nature of the brand. Worse still, convertible BMWs are often perceived as the car of the trophy wife.
Space and practicality
As a two-seat convertible, the Z4 is fighting a losing game when it comes to spaciousness and family appeal. There's no back seats at all, although the front seats are excellent for adults of any size.
Storage is decent, with a caveat. The boot is 310 litres, which is actually on a par with many supermini hatchbacks, but only with the roof in place. Lower the roof and this space is slashed to just 180 litres as the roof folds into a part of the boot. This is pretty small by any standard, even smaller than the boot on any city car.
The folding metal roof does, though, bring enhanced security compared to the soft-top of old. Fabric roofs are vulnerable to opportunist thefts of valuables and belongings from the vehicle, but the tin top gives the convertible experience without this risk.
The Z4 was tested by EuroNCAP in 2015, after the facelift, and scored just three stars although that doesn't quite tell the whole story. A 69% rating in occupant safety wasn't as a result of poor crash performance – in fact very few areas rated below 'good' – but the car has no autonomous emergency braking system.
Engines
There's two basic engines available on the Z4, although they're in different states of tune depending on the model. Both are 'Twin Power' turbocharged petrol engines.
The lower-capacity version is a 2.0-litre, four-cylinder unit. This is fitted to the base model sDrive18i car, producing 154hp. With a 0-60mph sprint time of 7.7s (7.9s for the automatic) and a top speed of 137mph, performance is adequate, but bear in mind that this is the most economical Z4, at 41.5mpg combined and 159g/km CO2.
A 181hp version of the same engine is fitted to the sDrive20i. Official emissions and economy statistics don't change from the sDrive18i, but it's around a second quicker to 60mph at 6.7s and the top speed moves up to 146mph.
The third version of this engine is in the sDrive28i. In this application it produces 241hp, which is enough to slash the acceleration figures to a rather brisk 5.5s 0-60mph (or 5.3s for the automatic) and invoke the classic BMW 155mph top speed limiter. The official fuel economy and emissions numbers are again 41.5mpg and 159g/km CO2, but it's not likely that this will be as frugal in real life as its lower-powered siblings.
The second engine is the 3.0-litre, twin turbocharged straight six, also available in two states of tune. As fitted to the sDrive35i model, it produces 302hp, springing to 60mph in dead-on 5 seconds (4.9s for the automatic), with the same 155mph limited top speed as the sDrive28i. Fuel economy takes a bit of a nosedive though, to just 31mpg, with emissions up at 211g/km.
Not to be confused with the sDrive35i, the top model is the sDrive35is. Here, that straight six engine produces 335hp and can only be paired with a seven-speed dual-clutch automatic, good for a 0-60mph time of 4.6s. Top speed is also limited to 155mph and the economy and emissions figures are as per the sDrive35i model.
Running costs
How the Z4 harms your pocket depends on whether you prefer the straight six engine or can make do with the four-cylinder option.
Although not truly bad, the Z4 only manages 41.5mpg in sDrive18i, 20i and 28i forms, and it's likely that this will be worse in real, day-to-day driving. The insurance group is similarly on the high side, with the sDrive18i sitting in group 34. The CO2 rating even for the entry level car gives it a £500 year one penalty for road tax too.
Move to the six-cylinder sDrive35i and sDrive35is and these costs skyrocket. First year VED is £1,200 - and if you get too careless with the specifications and send it over £40,000, you'll find yourself another £310 a year out of pocket. Insurance group is 42 or 43 and fuel economy is down to a best-case scenario of 31mpg.
Although not based on any other BMW, there's quite a few components derived from other models in the range, particularly older 3 Series cars. For the most part this makes servicing and repair fairly reasonable and it's a generally reliable car – but always be prepared for something more specific to the car failing and needing a costly replacement. Some consumables are pricey too.
Things to look out for
Like most of its siblings, the Z4 is a reasonably reliable car, with no common faults, problems or recalls affecting it in significant numbers. Many of the components and technologies it uses are available on other vehicles, so it's worth keeping an eye out on BMW recalls and faults in general as they may affect your car too.
You will need to ensure that the roof mechanism operates as it ought. This is a complex piece of machinery and it's designed to go up or down in 22 seconds at speeds of up to 25mph. If unlatched and operated but then taken above the recommended speed, some damage may occur as the roof acts like an air brake, putting stress into the moving components.
Rivals
As the Z4 is part coupe, part convertible, it has a number of rivals from different sectors. Key would be its mainstream German rivals, the Mercedes-Benz SLC and the Audi TT, but the Porsche 718 Boxster is one of the definitive cars of the sector and well worth considering as an alternative.
There's a few other sporting coupes and convertibles that would merit an inclusion on the same shopping list. The Ford Mustang is a major one, along with the Mazda MX-5 RF – which could be priced with every option for the same cost as the entry Z4.
Curiously the biggest rival might even be one of its own. The 2 Series comes in coupe and convertible forms, with similar but more frugal engines, at the same sort of prices and with more boot room and enough space for two more seats (although they're not very useful seats).
Depreciation warning
As the Z4 is no longer produced it's difficult to pin down depreciation precisely. Dealers may be offering cars at reduced prices to clear stock, for example, and the limited supply may make the Z4 more desirable in years to come (although without a halo M car, that's unlikely to be any time soon).
Regardless, three-year prices for the two-litre car are in the region of 42%. The three-litre models may be quicker, but the high running costs and relatively high specification of the cheaper cars could turn off second-hand buyers, so don't expect high returns.
