BMW Z4 review

“Do not try to do everything. Do one thing well.” So said Apple's Steve Jobs – and as the BMW Z4 shows, he had a point. Why? Well, the third-generation Z4 appears to have gone back to basics, with a greater focus on driver enjoyment.

You see, while the second-generation Z4 was more user-friendly to broaden its appeal, the main problem was its folding metal hard-top roof. It was great at keeping out the elements, but was also very heavy and dulled the car's handling.

This latest Z4 has a lighter fabric hood and redesigned suspension to improve handling. There's a choice of two petrol engines, and in March 2024 BMW made the most powerful version (the 335bhp Z4 M40i) available with a manual gearbox.

If that sounds like your kind of convertible two-seater, you'll probably be considering the Porsche 718 Boxster too. So how does the BMW Z4 get on against the Boxster and other sports car rivals? Read on to find out...

The entry-level BMW Z4 sDrive20i has a 194bhp 2.0-litre petrol engine. It picks up well from low revs and puts down its power easily, officially sprinting from 0-62mph in 6.6 seconds. That’s just 0.1sec slower than a 2.0-litre Mazda MX-5 184 but not a patch on the entry-level Porsche 718 Boxster (5.1 seconds).

Unfortunately, while BMW pitches the Z4 as a sports car, the sDrive20i fails to shine in important areas. It doesn’t have the zingy, free-revving attributes of the MX-5’s 2.0-litre petrol engine for example. Nor does it sound as exciting – you hear a dreary monotonous drone. It's only available with a sluggish eight-speed automatic gearbox, which doesn't help either. 

Thankfully, the range-topping Z4 M40i is much better. While there’s plenty of low-down muscle to bumble around effortlessly, the 335bhp 3.0-litre straight-six engine is just as eager to pull hard up to the limiter when you plant your foot on the accelerator pedal. It sounds much more invigorating than the four-cylinder sDrive20i and has a smooth free-revving nature.

You get an auto gearbox as standard, and it's snappier than the sDrive20i's, but we'd recommend taking up the option of a six-speed manual gearbox. The gearshift is a little notchy and requires more effort than in a Boxster, but once you get used to it, it’s a joy to use and is worth the added interaction.

Performance doesn’t suffer noticeably if you want to change gears yourself, with an official 0-62mph time of 4.6 seconds for the manual M40i and 4.5 seconds for the automatic.

Another reason to choose the M40i over the sDrive20i is that the less-powerful Z4 has grabby brakes that make it tricky to slow down smoothly in stop-start traffic. The M40i has beefier M Sport brakes that give you a better feel for what's going on below, giving you more confidence. Plus, the bespoke limited-slip differential helps put down power cleanly on the way out of corners.

Speaking of corners, the Z4 doesn't actually feel that sharp down a country road. The standard suspension fitted to the sDrive20i feels tuned more for motorway cruising comfort than canyon carving, allowing more body lean than in a Boxster. And because it's quite soft, the Z4 feels rather bouncy and wayward at the back end over B-road bumps.

The M adaptive suspension – which is standard on the M40i but costs extra on the sDrive20i – has a firmer Sport mode, which improves matters noticeably. It makes the car more stable and does a better job of absorbing mid-corner bumps. Manual M40is get tweaked suspension to deliver a slightly more engaging drive. 

Even so, the Z4’s hefty kerb weight means it's not as nimble as a Boxster, and the steering lacks the beautiful sense of connection with the front wheels you get with that rival. Its variable ratio rack means it initially responds quite slowly, but past a quarter of a turn of lock, the rate it turns the wheels suddenly ramps up, making it harder to place accurately on the road than the best sports cars.

As a result, the Z4 is best enjoyed when driving at moderate speeds, with its muscular power and relatively absorbent suspension cushioning over most surfaces in urban town roads and motorways.

At 70mph with the convertible roof up, there’s less wind and road noise than in a Boxster. If you open the roof (which takes 12 seconds with the push of a button) there's some buffeting even when the optional wind deflector is in place.

While the BMW Z4’s driving experience might not be compelling compared with rival sports cars, its interior is. The dashboard is angled towards you, creating a driver-focused environment with a low-slung seating position.

The driver's seat is reasonably supportive, while lumbar adjustment and full electric seat operation are standard on the M40i and optional on the sDrive20i. In the manual version, the pedals are offset to the right (although not as awkwardly far off centre as in a BMW M2) so it’s worth trying to see if it suits you first. 

Everything is reachable and all the controls are clearly structured and labelled. It's also impeccably finished, from the stitching on the standard leather seats to the sections of chrome and piano-black trims, and everything is beautifully incorporated. In fact, the Z4 looks plusher inside than a Porsche 718 Boxster.

The good news continues with the infotainment system: BMW's iDrive system is without a doubt the best on the market. It’s responsive, intuitive to use and easy to operate thanks to the rotary controller on the centre console.

It’s far less distracting than prodding the Boxster's touchscreen while you’re bowling along the motorway (although you can use the Z4's 10.3in screen as a touchscreen if you want).

All versions come with sat-nav, Bluetooth, DAB radio, Android Auto and Apple CarPlay. The optional Harman Kardon surround-sound system comes with extra speakers behind the seats that help drown out some of the exterior noise when the roof is down but it lacks the punch of the best stereos.

It's quite tricky to see the end of the Z4's long bonnet or what's behind you with the roof up. That's no great problem though: all versions come with front and rear parking sensors, and there’s the option of a rear-view camera. You get LED headlights as standard and adaptive LEDs are available with an options pack.

If you're very long in the leg you'll be more comfortable leg-room wise in the BMW Z4 than in a Porsche 718 Boxster. That said, there’s slightly less head room, although it's not tight in that area.

The long, narrow door pockets aren’t particularly practical, but they are a good size for a sports car (you don’t get any in a Mazda MX-5). There’s a handy covered cubby in front of the gearlever where you can charge your phone wirelessly, plus a decent-sized glovebox for extra bits and bobs.

While there are cup holders mounted inside the central armrest, you have to have the armrest covers open to use it. There’s a small amount of storage behind the seats and a cargo net with just enough space to shove a coat or spare pair of shoes.

The most impressive aspect of the Z4 when it comes to storage us the size of its boot – 281 litres. That's more than you get in a Boxster and it doesn't change when you drop the convertible roof.

We managed to fit in five carry-on suitcases in the Z4's boot (the same as in a VW Golf). There’s also a ski hatch between the seats to thread longer items through.

As a cash purchase, the entry-level BMW Z4 – the sDrive20i – costs significantly more than the most expensive Mazda MX-5. Meanwhile the more powerful M40i will cost slightly more than an entry-level Porsche 718 Boxster. That looks like good value considering the Boxster will have less kit and a smaller engine.

The Z4 is predicted to lose its value a little more quickly than a Boxster, although insurance and servicing costs are competitive. Fuel consumption is relatively palatable, and the sDrive20i’s official CO2 emissions are competitive.

Keeping things simple, there’s only one trim level available with each engine. The entry-level sDrive20i M Sport comes with plenty of standard equipment, including 18in alloy wheels, dual-zone climate control, cruise control, ambient lighting, heated front seats and leather upholstery.

The M40i is based on the M Sport but adds adaptive suspension, a limited-slip differential and brakes with blue calipers, plus 19in alloy wheels.

We can’t say for sure how reliable the Z4 will be because it wasn’t in our 2023 What Car? Reliability Survey. What we do know is that BMW came 12th out of 32 manufacturers, just ahead of Mazda in 13th, and far above Porsche in 20th.

In terms of crash protection, the Z4 achieved the maximum five-star rating when it was tested by Euro NCAP in 2019. It's likely to be safer than the MX-5, which scored four stars in 2015 (the rating has now expired), but we can't compare it accurately with the Boxster because that has never been rated.

The Z4 comes packed with safety kit, including front collision warning with automatic emergency braking (AEB) and a lane-departure warning system. You can add a Driving Assistant Package for more driver aids, including a system that can detect traffic crossing behind you as you’re reversing on to a road, lane-keeping assistance that steers you back into line, traffic-sign recognition and adaptive cruise control.

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