BMW Z4 2003 Review

What we liked
>> Engines and gearbox combinations
>> Road presence
>> Top down civility

Not so much
>> Steering
>> Steering
>> Did we mention steering?

OVERVIEW
Forget what you've read about BMW's Z4 being a replacement for the Z3. Not only has the performance bar been raised, but so too the dimensions of the car. It's bigger and faster than the at-times maligned Z3, and according to BMW it's armed, loaded and styled to herald in a new generation of roadsters.

Indeed, the Z4 has serious pretensions towards performance. It may not have an M-badge on its flame-surfaced flanks but perfect 50:50 weight distribution, two muscular inline six-cylinder engines -- the larger powerful enough to bump the car into its 250kmh speed limiter -- plus a swag of dynamic aids place the strictly two-seater four square in serious sportscar territory.

Still, with the entry-level autobox 2.5i priced at $78,500 before any options are ticked, and the six-speed manual 3.0i range-topper starting at a hefty $92,000, you'd have every right to expect the whole plot to be sharper. The good news is that it is... The bad news, in some aspects, it's perhaps a little too sharp!

FEATURES
The Z4 moves the BMW roadster into the new century in terms of interior space, amenities, and driver and safety aids. As well as ABS, the Z4 gets a full suite of electronic aids, four airbags and rollover protection. Oh - and the fastest fully automatic electric soft top on the market...

It's the rag top that heads the features list -- this is, after all, a roadster. Claimed to fold away sans human help in under 10 seconds, the fully automatic soft-top is standard across both models and is available in three colours to complement the Z4's selection of metallic and solid body colours. Fully lined and featuring a heated-glass rear window, the roof nests flush with the boot line; its front edge forming its own 'tonneau.' However, unlike some of the Z4's opposition, the soft top doesn't seriously handicap boot space. Indeed, even with the canvas down there's enough space for a weekend worth of (well-packed) luggage.

When up, there's substantially more headroom than the Z3, and wind noise is very well controlled, even at go-to goal speeds. Rear vision is good as well.

The interior of the car is somewhat spartan. A large convex brushed alloy beam dominates the fascia and the expansive textured dash-top is broken midway only by the optional 'Professional' level Navigation -- the swivel screen in up-to-date 16:9 format. On the driver side there's a single-hooded, twin-tubed , main instrument display -- very simple, very sportscar.

Minimalist climate controls are located centrally, low on the dash. They're easy to operate, and very functional, though not what many would expect from an $80,000-plus vehicle.

The Z4 is the first BMW, (but not the first BMW group car) to feature Electric Power Steering. Utilising electrically-actuated hydraulic assistance, EPS is claimed to offer fuel consumption savings as no power is drained when steering effort is not required (ie: when the wheels are straight ahead). The system is similar to that featured in the new Mini.

As well as assistance, feedback is also electronically 'monitored'. This set-up enables BMW to tie in not only engine and gearbox characteristics to its Sport mode Driver Dynamic Control software, but also steering.

Punch the console-mounted sport button on the Z4 and you dial up a change in ignition and fuel maps, gearchange points (in auto models) and steering effort and feedback. Read on for more of what this means to the nut behind the wheel.

With its long wheelbase, wide track and fashionably short overhangs, BMW's new Z4 is arguably the most palatable of the 21st century flame-surfaced new-gen Bavarians. Less likely to polarise opinion than the ground-breaking 7 Series, a measure of the success of the styling of the Z4 is that it's equally at home in a range of hues.

Whatever you read on the look, there's no doubt the car has road presence thanks to its elemental long-bonnet and wheel-at-each-corner looks.

MECHANICAL
Under the Z4's long alloy bonnet resides two of the best inline sixes on the planet. Both bi-VANOS infinitely-variable cam timed units, the fuel-injected 24-valve powerplants are muscular and smooth -- just as we've come to expect from BMW.

While the urge of the 170kW 3.0i is infectious, the sweet spinning 141kW 2.5i powerplant delivers enough pace to keep most drivers smiling. Indeed, even in five-speed autobox guise (most 2.5is will arrive in Oz so equipped) performance is spirited.

Standard gearbox for the 3.0lt Z4 is a wonderful short-throw close-ratio six-speed manual. The engine's happy for you to use the old 1-3-5-6 short-shift routine, but I found myself going all the way up and down the box just for fun.

There's a five-speed manual box available as an option on the 2.5i, and likewise a five-speed self-shifter for the 3.0i. No SMG at this juncture, although BMW's smartest gearbox is offered as an option to European buyers of the new car.

A conventional front-engined rear wheel drive layout, the Z4 gets vented discs on all four corners. The 3.0i gets uprated discs with the front set-ups a full 300mm in diameter.

Suspension is based on the critically-acclaimed 3 Series but modified for an even sportier feel. An optional BMW M Technic sports suspension is offered which lowers the car a further 15mm.

COMFORT
We spent most of our time in the 3.0i range-topping Z4 and consequently were rewarded with a reasonable level of goodies. That said, even the 'stripper' 2.5i is well equipped.

As is the case with all BMWs, basic ergonomics are good though drivers on the taller end of the scale tended to spend a little more time getting settled.

Sports seats are standard in both models, with leather, seat heating and electric adjustment also standard. The steering wheel is adjustable for height and reach, so you'd be hard-pressed not to find the spot you like.

Although offering more room than the Z3, the new car still places a premium on elbow room, especially with two hefty fellows onboard.

With the roof down there's little in the way of buffeting, even at high speeds, and there's no need to shout, nor max out the audio to hear. Indeed, though there's an optional wind deflector that fits between the fixed twin roll-over hoops, we'd suggest you save your money -- it's hardly needed.

As noted above, with the roof up, the Z4 offers saloon-like comfort. There's a hardtop coming, but truth be known if you're finding fault with the stock soft-top then perhaps a roadster is not for you.

Unlike some roadsters there's also plenty of space for bits and pieces -- even cup/can holders make it into the standard spec. A number of trim levels are offered, with the 2.5i and 3.0i getting a mix of leatherette and leather surfaces with alloy accents as standard. Optional is a full leather 'New England' interior that adds dead cow to the tops of the doors et al. Suffice it to say, criticisms about the spartan nature of the dash aside, the standard trim is classy and comfortable.

SAFETY
As you'd expect from one of the world's top marques safety is high on the priorities list.

In terms of driver safety aids, the Z4 features front and side driver and passenger airbags, and the myriad of behind-the-scenes tweaks upon which BMW prides itself.

With a base structure more than twice as stiff as the Z3, it's clear that considerable attention has been paid to the basic build values of the car. Complex steel and aluminium deformable structures are featured in the chassis design and high strength alloys have been used where desirable.

Particular attention has been paid to rollover protection, with the Z4's A-pillars and windscreen frame forming a rollover frame in front of the occupants. Sturdy fixed steel rollover bars are combined with a massive cross member to complete the safety cell behind.

Both Z4 models get a full complement of BMW driver aids as standard equipment -- ABS, Driver Dynamic Control, Automatic Stability Control and Traction, Corner Braking Control and Dynamic Stability Control with Dynamic Traction Control.

Sold as a safety plus, but also benefitting the Z4 in terms of space utilisation and mass, is the adoption of 'run flat' rubber on the Z4. Following the lead of the Mini, the Z4 features neither spare tyre nor jack and tyre changing tools and all standard and optional factory wheel/rubber combinations are run flat systems.

Tyre pressure is monitored automatically, and if a puncture does occur the run flat rubber offers an envelope of 150km (at a maximum of 80kmh) to get yourself out of trouble. No official word on the replacement cost of the tyres (they are not repairable) but BMW staffers stated at the launch that prices are commensurate with standard tyres in the same sizes.

For the record, 16-inch and 17-inch hoops are standard equipment on the 2.5i and 3.0i respectively. There are 18-inch wheel/tyre combinations available as options on both models.

COMPETITORS
BMW is not shy in identifying the field in which the Z4 is set to play. Perpetual competitors Mercedes Benz and Porsche are high on the list with their SLK and Boxster models respectively. Audi's TT Roadster should also be flagged as a 'what if'.

In terms of performance, claimed acceleration and top speed numbers for the Z4 3.0i place it between the Boxster and Boxster S and 'up there' with the very fastest of the SLKs.

That said even with a serious tilt at the options list, a 'loaded' 3.0i Z4 will easily undercut the $108,500 asked for the Boxster or $112.074 SLK320, let alone the likes of the $133K-plus Boxster S.

The base SLK and Z4 are closer in dollar terms, although the Z4's likely to prove a much sportier drive. And I'd back a 2.5i Z4 to have the measure against the SLK200K; a car that at $86,174 is close to 10% more expensive.

The 2.5i compares favourably to the $80,900 basic version of the 1.8lt turbocharged Audi also.

Note, however, that the Z4s are offered at a hefty premium over BMW's own benchmark 3 Series Coupes, and, of course, the now retired Z3s.

ON THE ROAD
There's no doubt the new Z4 offers serious go (0-100kmh in 5.9sec in the case of the 3.0i), high levels of roadholding and very impressive drivetrains. However there's a question mark over the car's very sharp steering.

BMW's launch location for the Z4 in the granite country around Toowoomba, west of Brisbane, presented a mixture of challenging and at times downright fast roads. Almost universally, however, the roads were liberally dosed with whoops, bumps, berms and the like.

The good news is that the Z4s proved very tight over the route with not a hint of scuttle shake, a bugbear of the flexy flyer Z3. Suspension set-up overall was good too, on the firm side of sporty but never jarring (nor uncomfortable) and beautifully damped.

But the cars, especially those wearing 18-inch wheels, were at times a handful on the bumpy roads, keeping the drivers busy with a propensity to tramline on some surfaces.

This was more so the case when Sport mode was selected via DDC. Woolly in a straight line, the steering seemed almost over-servoed off-centre leading to the sort of constant correction at the wheel that's both unsettling and unwanted.

Ironically, the sharp steering response didn't necessarily translate to sharp turn-in. Indeed, as is often the case nowadays, balance when pushing on was edging towards slight understeer.

That said there's no question the car has truckloads of grip, and for our money the smaller engined cars were a degree sweeter overall than the big bangers -- perhaps thanks to a little less mass over the front wheels, or maybe due to different wheel/tyre combos?

While we'll reserve our final judgement on the driver's choice until we've had the chance to drive the combatants back to back, an early seat of the pants impression still has the Z4 with some ground to make up to better Porsche's impressive Boxster.

Whatever the case, there's no doubt the Z4's a much more convincing sportster than the outgoing Z3: indeed, BMW now has a serious player at the sharp end of the roadster segment...

But a Boxster beater? That's still to be decided... And we can't wait for the bout...

BOTTOM LINE A fantastic sports convertible with a bad case of the wanders.

Sinkers is right: The steering is crook. On the road the car's tendency to wander is disconcerting and distracting. Under braking the Z4's desire to follow any hint of road camber can result in an impromptu lane change if the driver's not attentive. One 'hands-off' experiment on one of Melbourne's wider roads late at night resulted in not one but two lane changes -- first left then right.

It's a problem that's immediately understandable if you take the Z4 for a blast. Hit the back roads with intent and the Z4's once wayward steering becomes responsive, communicative and inch perfect. There's an underlying addictiveness to the Z4's raw ability; it voracious appetite for corners, the straight six's silky smooth power delivery and the chassis' bear-hug grip on the road.

Styling's become a sore point with current generation BMWs, yet we're drawn to the Z4's new clothes. Forget marketing hyperbole about flame-surfacing and what-not, look instead at the purposeful aggression around the rear, especially the bulging wheel-arches.

The front end is unmistakable, whether you like it or not, and the interior works well. There are those who accuse the inside of being spartan and too basic for a $100k convertible, but that's exactly what we like about it.

Passion aside, practicalities are in adequate supply for a sunshine cruiser. The boot's big enough to swallow a couple of duffel bags, and there's enough cubby holes inside for CDs, mobile phones and keys. But that's not why you buy a Z4.

The Z4 is a real driver's car... when you unleash the potential. But when there's transport and travelling to be done, its overly reactive steering is simply too much to put up with -- especially in the rarefied air around $100,000.