The BMW Z4 (E85) 2.2i Steptronic, produced from 2003 to 2006, represents the entry point into the first generation of the Z4 roadster series. Positioned as the base model, it offered an accessible price point for those desiring BMW’s open-top driving experience. The E85 Z4, replacing the Z3, aimed to provide a more refined and modern driving experience, focusing on improved handling and a more contemporary design. The 2.2i variant, equipped with the Steptronic automatic transmission, catered to drivers prioritizing comfort and ease of use over outright performance, though it still delivered a distinctly BMW driving feel. It was built on the E85 platform, a rear-wheel drive platform that emphasized balanced handling.
Technical Specifications
| Brand | BMW |
| Model | Z4 |
| Generation | Z4 (E85) |
| Type (Engine) | 2.2i (170 Hp) Steptronic |
| Start of production | 2003 |
| End of production | 2006 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Roadster |
| Seats | 2 |
| Doors | 2 |
| Fuel consumption (urban) | 11.4 l/100 km (20.6 US mpg) |
| Fuel consumption (extra urban) | 5.8 l/100 km (40.6 US mpg) |
| Fuel consumption (combined) | 7.7 l/100 km (30.5 US mpg) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 8.3 sec |
| Acceleration 0 – 62 mph | 8.3 sec |
| Acceleration 0 – 60 mph | 7.9 sec |
| Maximum speed | 221 km/h (137.32 mph) |
| Weight-to-power ratio | 7.8 kg/Hp |
| Weight-to-torque ratio | 6.3 kg/Nm |
| Power | 170 Hp @ 6100 rpm |
| Torque | 210 Nm @ 3500 rpm (154.89 lb.-ft. @ 3500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M54B22 |
| Engine displacement | 2171 cm3 (132.48 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 80 mm (3.15 in.) |
| Piston Stroke | 72 mm (2.83 in.) |
| Compression ratio | 10.8:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Engine oil capacity | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Coolant capacity | 8.8 l (9.3 US qt | 7.74 UK qt) |
| Kerb Weight | 1325 kg (2921.12 lbs.) |
| Max. weight | 1550 kg (3417.17 lbs.) |
| Max load | 225 kg (496.04 lbs.) |
| Trunk (boot) space – minimum | 300 l (10.59 cu. ft.) |
| Fuel tank capacity | 55 l (14.53 US gal | 12.1 UK gal) |
| Length | 4091 mm (161.06 in.) |
| Width | 1781 mm (70.12 in.) |
| Height | 1299 mm (51.14 in.) |
| Wheelbase | 2495 mm (98.23 in.) |
| Front track | 1473 mm (57.99 in.) |
| Rear track | 1523 mm (59.96 in.) |
| Minimum turning circle | 9.8 m (32.15 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears | 5 |
| Gearbox type | Automatic transmission |
| Front suspension | Spring Strut |
| Rear suspension | Coil spring |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 205/55 R16 |
| Wheel rims size | 7J X 16 |
Powertrain & Engine Architecture
The heart of the Z4 2.2i Steptronic is the M54B22, a 2.2-liter inline-six engine. This engine is a naturally aspirated powerplant known for its smooth operation and linear power delivery. It utilizes a double overhead camshaft (DOHC) valvetrain with four valves per cylinder, contributing to its respectable power output for its displacement. Fuel delivery is managed by a multi-port fuel injection system, ensuring precise fuel metering. The M54 engine family, widely used across various BMW models of the era, is renowned for its durability and relatively straightforward maintenance. The Steptronic automatic transmission is a 5-speed unit, offering smooth shifts and convenience. While not as sporty as a manual transmission, it provided a more relaxed driving experience, aligning with the target audience for this trim level. The transmission’s programming prioritized comfort and fuel efficiency over aggressive shifting.
Driving Characteristics
The Z4 2.2i Steptronic delivers a comfortable and engaging driving experience. With 170 horsepower and 155 lb-ft of torque, acceleration is adequate, reaching 0-60 mph in around 7.9 seconds. However, it’s noticeably slower than the more powerful Z4 3.0i models. The automatic transmission, while smooth, does slightly diminish the sense of control compared to the available manual gearbox. The gear ratios are tuned for everyday usability, providing sufficient power for highway cruising and city driving. The rear-wheel drive configuration contributes to balanced handling, and the relatively lightweight construction of the E85 chassis enhances agility. Compared to the 6-speed manual version, the Steptronic offers less driver involvement but greater ease of use, particularly in stop-and-go traffic.
Equipment & Trim Levels
The 2.2i Steptronic came standard with features such as power windows, power locks, and a basic audio system. Interior upholstery typically consisted of cloth seats, although leather options were available. The dashboard layout was functional and driver-focused, with clear instrumentation. Optional extras included a premium sound system, heated seats, automatic climate control, and a sport package that added features like sport seats and a sport suspension. The trim level was generally considered the entry-level offering, focusing on providing the core Z4 experience without the added luxuries of higher-spec models.
Chassis & Braking
The Z4 E85 chassis is a robust and well-engineered platform. The 2.2i model utilized a spring strut front suspension and a coil spring rear suspension. Braking duties were handled by ventilated discs on all four wheels, providing adequate stopping power. ABS (Anti-lock Braking System) was standard, enhancing safety. The suspension tuning was geared towards comfort, offering a compliant ride quality. Compared to the sport suspension option available on higher trims, the standard suspension provided a softer and more forgiving ride.
Market Reception & Comparison
The Z4 2.2i Steptronic was generally well-received by automotive critics as an accessible entry point into the Z4 range. It was praised for its comfortable ride, smooth engine, and engaging handling. However, some critics noted that the 2.2-liter engine lacked the punch of the larger 3.0-liter variants. Fuel economy was considered respectable for a sports car, averaging around 30.5 US mpg in combined driving. Compared to the Z4 3.0i, the 2.2i offered a lower price point but sacrificed performance. Compared to the Z4 2.5i, it offered similar performance but with a smaller engine displacement and potentially lower maintenance costs.
Legacy
The M54B22 engine, found in the Z4 2.2i, has proven to be a reliable and durable powerplant. With proper maintenance, these engines can easily exceed 150,000 miles. The Steptronic automatic transmission is also generally reliable, although like any automatic transmission, it requires regular fluid changes. In the used car market, the Z4 2.2i Steptronic represents an affordable way to experience BMW roadster ownership. While not the fastest or most feature-rich Z4 variant, it offers a compelling combination of style, comfort, and driving enjoyment. Its relative simplicity and proven mechanicals make it a popular choice for enthusiasts seeking a classic BMW roadster experience without breaking the bank.