A look back at the Z series lineage

BMW's roadster models boast over 60 years of history. The first Z series model, the "Z1," appeared in 1989 as its modern production version. It was characterized by its unique vertically sliding side doors, and 8,000 units were produced over two years until 1991.

The second generation, the "Z3," arrived in 1995. This model, combining a compact body with a lightweight soft top, became immensely popular worldwide, selling 297,000 units over seven years.

The theme for the new Z4, the sixth generation of the Z series debuting in March 2019, is "the coexistence of beauty and dynamism." It's designed as a two-seater roadster with a beautiful long-hood, short-deck body, powered by potent six-cylinder and four-cylinder engines, and featuring a lightweight soft top. To assess its performance, I participated in a test drive event held on a familiar winding road.

Test drive the 3-liter inline-6 powered M40i

The new model's dimensions are 4,335mm long, 1,865mm wide, and 1,305mm high, with a curb weight of 1,570kg. Compared to the previous generation, the body is 85mm longer, 75mm wider, and 15mm taller, while the wheelbase is 25mm shorter (2,470mm), and the front and rear tracks are wider by 100mm and 75mm, respectively. By switching from a hardtop to a lightweight soft top, the aim was to enhance agility and handling.

The exterior design maintains the classic sports car style, with two seats positioned at the rear of a long hood. The headlights, arranged along the sides of the front body, give the traditional kidney grille a wider appearance, with a new mesh design inside. A press line originating from the air breather behind the front wheels flows upwards, creating a dynamic side view characteristic of a roadster.

The model I tested was the "Z4 M40i," currently the top-tier model equipped with an inline-6 engine. The B58B30C 3-liter inline-six TwinPower Turbo engine at its heart produces a maximum output of 340ps (250kW) at 5,000rpm and a peak torque of 500Nm between 1,600-4,500rpm. Paired with an 8-speed automatic transmission, it's officially rated to accelerate from 0-100km/h in 4.6 seconds. To illustrate its performance, the new Z4 completed a lap of the Nürburgring Nordschleife in 7 minutes and 55 seconds, a circuit where the sporty BMWM2 Competitionrecorded a time of 7 minutes and 52 seconds.

The ride quality remains high even with the top down, a hallmark of BMW roadsters

The test drive began early in the morning at a parking lot over 1,000 meters above sea level, where the temperature was low. Initially, I started with the top up. Even accounting for the downhill gradient and the engine not reaching very high RPMs, I immediately noticed the remarkable quietness inside the cabin.

The cabin was comfortable, effectively blocking out unpleasant road noise and wind noise. When I shifted to manual mode and selected a lower gear to rev the engine higher, only the refined sound of the six-cylinder engine could be heard as transmitted sound.

Just before reaching the lower parking lot, I opened the roof using the button below the shift lever. The new model can open or close the roof in just 10 seconds at speeds below 50km/h, which is remarkably fast compared to the 20 seconds it took the previous generation.

The ride quality doesn't degrade even with the top down, which is truly characteristic of a BMW roadster. On an uphill corner taken in third gear at moderate speed, the combination of the standard variable sport steering, adaptive M sport suspension, and M sport differential worked seamlessly, allowing me to perfectly navigate the apex of the corner with a single steering input. The sensation of the car rotating from the rear and propelling itself forward was directly transmitted to my body, securely held by the deeply bolstered sport seats, which was a delight.

These characteristics are particularly pronounced in Sport mode. Simultaneously, when the roof is closed, the "pop-pop" sound on deceleration, which I hadn't particularly noticed before, now reaches my ears directly from the exhaust, bringing an involuntary smile to my face.

When I pressed the accelerator, the engine revved freely up to the 7,000rpm redline on the tachometer. Furthermore, since peak torque is available from 1,600rpm, there was absolutely no stress even during low-speed city driving. The engine characteristics were flat, with vehicle speed accurately proportional to accelerator input. However, I wonder if it's just me, but I feel that older naturally aspirated engines offered a more exhilarating sensation when revving higher, as power continued to build.

Trunk capacity is 281 liters, regardless of roof position

Turning to the interior, the new digital instrument cluster, similar to the "8 Series" and "3 Series," features a speedometer and tachometer rotating in opposite directions, with navigation information displayed in between. It also incorporates the information display on the center console.

Practicality is also well-addressed, with a usable trunk capacity of 281 liters regardless of the roof's position, and luggage nets behind the seats.

Furthermore, it offers modern car features such as the "BMW Intelligent Personal Assistant," an AI-powered voice control system that allows for natural conversational commands and the selection of personalized wake words, and an optional high-fidelity "harman/kardon Surround Sound System" to reduce fatigue on long drives.

The model range includes four variants: three with a 2.0-liter inline four-cylinder engine producing 197ps (145kW) and 320Nm, and one with a 3.0-liter inline-six engine. Prices range from 5.66 million yen for the standard "Z4 sDrive20i" to 8.35 million yen for the "Z4 M40i" I tested.