The BMW Z4 (E89) 28i sDrive, produced from 2011 to 2013, represented a significant iteration of BMW’s popular two-seater roadster. Positioned as a mid-range offering within the E89 Z4 lineup, it bridged the gap between the entry-level 23i and the performance-oriented 35i models. The 28i was designed to appeal to drivers seeking a balance of sporty handling, respectable power, and relative fuel efficiency in a premium package. It was primarily marketed towards enthusiasts looking for an engaging driving experience without the higher price tag or more aggressive tuning of the top-tier variant. The E89 generation itself was a departure from the previous Z4 (E85) model, adopting a more sophisticated and luxurious character while retaining the core roadster experience.
Technical Specifications
| Brand | BMW |
| Model | Z4 |
| Generation | Z4 (E89) |
| Type (Engine) | 28i (245 Hp) sDrive |
| Start of production | 2011 |
| End of production | 2013 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Roadster |
| Seats | 2 |
| Doors | 2 |
| Fuel consumption (urban) | 9.1 l/100 km (25.8 US mpg, 31 UK mpg, 11 km/l) |
| Fuel consumption (extra urban) | 5.5 l/100 km (42.8 US mpg, 51.4 UK mpg, 18.2 km/l) |
| Fuel consumption (combined) | 6.8 l/100 km (34.6 US mpg, 41.5 UK mpg, 14.7 km/l) |
| CO2 emissions | 159 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 5.7 sec |
| Acceleration 0 – 62 mph | 5.7 sec |
| Acceleration 0 – 60 mph | 5.4 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Weight-to-power ratio | 6 kg/Hp, 166.1 Hp/tonne |
| Weight-to-torque ratio | 4.2 kg/Nm, 237.3 Nm/tonne |
| Power | 245 Hp @ 5000-6500 rpm |
| Power per litre | 122.7 Hp/l |
| Torque | 350 Nm @ 1250-4800 rpm (258.15 lb.-ft. @ 1250-4800 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | N20B20A |
| Engine displacement | 1997 cm3 (121.86 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 90.1 mm (3.55 in.) |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Twin-power turbo, Intercooler |
| Engine oil capacity | 5 l (5.28 US qt | 4.4 UK qt) |
| Kerb Weight | 1475 kg (3251.82 lbs.) |
| Max. weight | 1730 kg (3814 lbs.) |
| Max load | 255 kg (562.18 lbs.) |
| Fuel tank capacity | 55 l (14.53 US gal | 12.1 UK gal) |
| Length | 4239 mm (166.89 in.) |
| Width | 1790 mm (70.47 in.) |
| Height | 1291 mm (50.83 in.) |
| Wheelbase | 2496 mm (98.27 in.) |
| Front track | 1511 mm (59.49 in.) |
| Rear track | 1559 mm (61.38 in.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears | 6 |
| Gearbox type | Manual transmission |
Powertrain & Engine Architecture
The heart of the Z4 28i sDrive is the BMW N20B20A 2.0-liter inline-four cylinder engine. This engine is a key member of BMW’s modular engine family, utilizing direct fuel injection, a single twin-scroll turbocharger, and variable valve timing (VANOS) and valve lift (Valvetronic) technologies. These features work in concert to deliver a broad torque curve and efficient power delivery. The N20 engine is known for its responsiveness and relatively smooth operation for a turbocharged four-cylinder. The 28i variant produces 245 horsepower and 350 Nm (258 lb-ft) of torque. The engine is longitudinally mounted, driving the rear wheels. The standard transmission for the 28i was a six-speed manual, but an eight-speed automatic transmission was also available as an option. The automatic transmission offered smoother shifts and enhanced fuel economy, but at the expense of some driver engagement.
Driving Characteristics
The Z4 28i sDrive offered a compelling driving experience, balancing performance and comfort. With 245 hp, acceleration from 0 to 60 mph took approximately 5.4 to 5.7 seconds, depending on transmission and testing conditions. While not as brutally quick as the 35i model, the 28i provided ample power for spirited driving on both winding roads and open highways. The rear-wheel-drive layout contributed to a balanced chassis and predictable handling. The six-speed manual transmission offered precise shifts and a direct connection to the engine, while the optional eight-speed automatic provided seamless gear changes. The suspension, tuned for a balance of comfort and control, delivered a relatively compliant ride without sacrificing handling precision. Compared to the 35i, the 28i felt less urgent in its acceleration, but it also offered a more manageable and accessible powerband for everyday driving.
Equipment & Trim Levels
The Z4 28i sDrive came reasonably well-equipped as standard. Typical features included leatherette upholstery, power-adjustable seats, automatic climate control, a BMW iDrive infotainment system with a 6.5-inch display, and a premium sound system. Optional extras were plentiful, allowing buyers to customize their Z4 to their preferences. Popular options included leather upholstery, heated seats, navigation system, a Harman Kardon sound system, and various driver-assistance features. The interior design was focused on the driver, with a cockpit-style layout and intuitive controls. The overall ambiance was one of understated luxury and sporty refinement.
Chassis & Braking
The Z4 E89 utilized a MacPherson strut front suspension and a multi-link rear suspension. This setup provided a good balance of ride comfort and handling precision. The 28i model typically featured stabilizer bars to reduce body roll during cornering. Braking duties were handled by ventilated disc brakes at all four corners. ABS (Anti-lock Braking System) was standard, providing enhanced stopping power and stability. The steering system employed a rack-and-pinion setup, offering precise and responsive steering feel. The standard tire size was 225/45 R17, mounted on 8J x 17 inch alloy wheels.
Market Reception & Comparison
The Z4 28i sDrive was generally well-received by automotive critics. It was praised for its balanced performance, comfortable ride, and refined interior. Critics noted that it offered a compelling alternative to the more expensive 35i model, providing a similar driving experience at a lower price point. Fuel economy was also a strong point, with the 28i achieving around 34.6 US mpg in combined driving. Compared to the 23i, the 28i offered a significant power boost, making it a more engaging and enjoyable driving experience. However, the 28i was often seen as a compromise, lacking the outright performance of the 35i but costing more than the 23i.
Legacy
The BMW Z4 E89 28i sDrive has proven to be a relatively reliable vehicle in the used car market. The N20 engine, while not without its potential issues (such as oil leaks and timing chain wear), is generally considered durable when properly maintained. The availability of parts and service is good, thanks to the widespread popularity of the BMW brand. Today, the E89 Z4 28i represents a stylish and engaging roadster option for enthusiasts seeking a well-rounded and relatively affordable two-seater. Its blend of performance, comfort, and fuel efficiency continues to appeal to a wide range of drivers.
