The BMW Z4 M40i (G29 LCI), introduced in November 2022 as part of the G29 Z4’s Life Cycle Impulse (LCI) facelift, represents the performance pinnacle of the third-generation Z4 roadster. Positioned as the flagship variant, it builds upon the foundation laid by the G29 platform, which debuted in 2019, offering a significant step up in power and driving dynamics compared to the base 2.0-liter models. Production continued through March 2026, solidifying its place as a modern interpretation of BMW’s long-standing roadster tradition. The LCI updates brought subtle styling revisions, enhanced technology, and refinements to the engine and chassis.
Technical Specifications
| Brand | BMW |
| Model | Z4 |
| Generation | Z4 (G29 LCI, facelift 2022) |
| Type (Engine) | M40i (382 Hp) Steptronic |
| Start of production | November, 2022 |
| End of production | March, 2026 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Roadster |
| Seats | 2 |
| Doors | 2 |
| Fuel consumption (economy) – urban (EPA) | 10.2 l/100 km (23.1 US mpg, 27.7 UK mpg, 9.8 km/l) |
| Fuel consumption (economy) – extra urban (EPA) | 8.1 l/100 km (29 US mpg, 34.9 UK mpg, 12.3 km/l) |
| Fuel consumption (economy) – combined (EPA) | 9.4 l/100 km (25 US mpg, 30.1 UK mpg, 10.6 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 60 mph | 3.9 sec |
| Maximum speed | 250 km/h (155.34 mph), Electronically limited |
| Weight-to-power ratio | 4.2 kg/Hp, 237.7 Hp/tonne |
| Weight-to-torque ratio | 3.2 kg/Nm, 311.1 Nm/tonne |
| Power | 382 Hp @ 5800-6500 rpm |
| Power per litre | 127.4 Hp/l |
| Torque | 500 Nm @ 1800-5000 rpm (368.78 lb.-ft. @ 1800-5000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | B58B30O1 |
| Engine displacement | 2998 cm3 (182.95 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 82 mm (3.23 in.) |
| Piston Stroke | 94.6 mm (3.72 in.) |
| Compression ratio | 10.2:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Twin-power turbo, Intercooler |
| Valvetrain | VALVETRONIC, Double-VANOS |
| Engine oil capacity | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Kerb Weight | 1607 kg (3542.83 lbs.) |
| Max. weight | 1860 kg (4100.6 lbs.) |
| Max load | 253 kg (557.77 lbs.) |
| Trunk (boot) space – minimum | 280 l (9.89 cu. ft.) |
| Fuel tank capacity | 52 l (13.74 US gal | 11.44 UK gal) |
| Length | 4337 mm (170.75 in.) |
| Width | 1864 mm (73.39 in.) |
| Width including mirrors | 2024 mm (79.69 in.) |
| Height | 1304 mm (51.34 in.) |
| Wheelbase | 2470 mm (97.24 in.) |
| Front track | 1594 mm (62.76 in.) |
| Rear (Back) track | 1589 mm (62.56 in.) |
| Ride height (ground clearance) | 119 mm (4.69 in.) |
| Drag coefficient (Cd) | 0.29-0.35 |
| Minimum turning circle (turning diameter) | 11 m (36.09 ft.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 8 gears, automatic transmission Steptronic |
| Front suspension | Spring Strut, Transverse stabilizer |
| Rear suspension | Independent multi-link spring suspension with stabilizer |
| 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 | Front wheel tires: 255/40 R18; 255/35 R19 Rear wheel tires: 275/40 R18; 275/35 R19 |
| Wheel rims size | Front wheel rims: 9J x 18; 9J x 19 Rear wheel rims: 10J x 18; 10J x 19 |
Powertrain & Engine Architecture
At the heart of the Z4 M40i lies the BMW B58B30O1 3.0-liter inline-six engine. This engine is a member of the modular B-series engine family, known for its robust construction and high output. The B58 utilizes a single, twin-scroll turbocharger with intercooling, direct fuel injection, and BMW’s VALVETRONIC variable valve timing and Double-VANOS variable camshaft timing systems. These technologies work in concert to deliver a broad torque curve and responsive performance. The engine produces 382 horsepower at 5800-6500 rpm and 368 lb-ft of torque from 1800-5000 rpm. The engine is paired with BMW’s 8-speed Steptronic automatic transmission, which features optimized shift programming for both spirited driving and fuel efficiency. The transmission offers both automatic and manual shift modes, with paddle shifters available for driver control.
Driving Characteristics
The Z4 M40i delivers a distinctly sporty driving experience. The combination of the powerful inline-six engine and the responsive Steptronic transmission results in brisk acceleration – 0 to 60 mph in just 3.9 seconds. The rear-wheel-drive configuration and well-tuned chassis contribute to agile handling and a connected feel. Compared to the 2.0-liter Z4 variants, the M40i offers significantly more power and torque throughout the rev range, resulting in effortless overtaking and a more engaging driving experience. The 8-speed transmission’s gear ratios are optimized for both acceleration and cruising, providing a balance between performance and efficiency. While the 2.0-liter models prioritize fuel economy, the M40i is geared towards drivers who prioritize performance and driving enjoyment.
Equipment & Trim Levels
The Z4 M40i came standard with a comprehensive list of features, including leather upholstery, a premium sound system, a digital instrument cluster, and BMW’s iDrive infotainment system with a touchscreen display. Available options included adaptive suspension, M Sport brakes, a head-up display, and various interior trim options. Exterior features such as M Sport aerodynamic styling, larger wheels, and upgraded exhaust systems were also available. The interior design focused on a driver-centric layout, with controls positioned for easy access and a sporty aesthetic.
Chassis & Braking
The Z4 M40i features a lightweight chassis with a focus on rigidity and balance. The suspension utilizes a spring strut design at the front and an independent multi-link setup at the rear, both incorporating stabilizer bars to minimize body roll. The braking system consists of ventilated discs at all four corners, providing ample stopping power. The M Sport brakes, available as an option, offer even greater stopping performance and fade resistance. The steering system is an electric power-assisted rack and pinion, providing precise and responsive steering feel.
Market Reception & Comparison
The Z4 M40i was generally well-received by automotive critics, who praised its powerful engine, agile handling, and refined interior. It was often compared favorably to competitors such as the Porsche 718 Boxster and the Mercedes-Benz SLC. While the Z4 M40i offered slightly less overall refinement than the Porsche, it provided a compelling combination of performance, value, and driving enjoyment. Fuel economy was respectable for a performance roadster, averaging around 25 mpg in combined driving. Reliability reports have been generally positive, with the B58 engine proving to be a durable and dependable powerplant.
Legacy
The Z4 M40i (G29 LCI) represents a significant step forward for BMW’s roadster lineup. Its potent engine, engaging driving dynamics, and modern features have cemented its place as a desirable performance car. On the used car market, the Z4 M40i holds its value well, attracting buyers who appreciate its blend of performance and luxury. The B58 engine’s reputation for reliability further enhances its appeal, making it a compelling choice for enthusiasts seeking a modern roadster experience.
