The BMW 4 Series Coupe (F32), specifically the 420i variant produced from 2017 to 2020 following the facelift, represents a key entry point into the 4 Series lineup. Positioned as a more accessible alternative to the higher-performance 430i and 440i models, the 420i offered a blend of BMW’s renowned driving dynamics with improved fuel efficiency and a lower price tag. This generation of the 4 Series, built on the F32 platform, aimed to deliver a sporty and stylish coupe experience, appealing to buyers seeking a premium vehicle without the expense of its more powerful siblings. The 420i was primarily marketed towards individual buyers and young professionals looking for a sophisticated and engaging driving experience.
Technical Specifications
| Brand | BMW |
| Model | 4 Series |
| Generation | 4 Series Coupe (F32, facelift 2017) |
| Type (Engine) | 420i (184 Hp) |
| Start of production | 2017 |
| End of production | 2020 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 7.7-8.1 l/100 km (30.5 – 29 US mpg) |
| Fuel consumption (extra urban) | 4.7-4.9 l/100 km (50 – 48 US mpg) |
| Fuel consumption (combined) | 5.8-6.1 l/100 km (40.6 – 38.6 US mpg) |
| CO2 emissions | 134-141 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 7.3 sec |
| Acceleration 0 – 62 mph | 7.3 sec |
| Acceleration 0 – 60 mph | 6.9 sec |
| Maximum speed | 236 km/h (146.64 mph) |
| Emission standard | Euro 6 |
| Weight-to-power ratio | 8 kg/Hp, 124.7 Hp/tonne |
| Weight-to-torque ratio | 5.1 kg/Nm, 196.6 Nm/tonne |
| Power | 184 Hp @ 5000 rpm |
| Torque | 290 Nm @ 1350-4600 rpm (213.89 lb.-ft. @ 1350-4600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | B48B20A |
| Engine displacement | 1998 cm3 (121.93 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 82 mm (3.23 in.) |
| Piston Stroke | 94.6 mm (3.72 in.) |
| Compression ratio | 11:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Twin-power turbo, Intercooler |
| Engine oil capacity | 5.25 l (5.55 US qt | 4.62 UK qt) |
| Coolant | 7.8 l (8.24 US qt | 6.86 UK qt) |
| Kerb Weight | 1475 kg (3251.82 lbs.) |
| Max. weight | 1995 kg (4398.22 lbs.) |
| Max load | 520 kg (1146.4 lbs.) |
| Trunk (boot) space – minimum | 445 l (15.72 cu. ft.) |
| Fuel tank capacity | 60 l (15.85 US gal | 13.2 UK gal) |
| Max. roof load | 75 kg (165.35 lbs.) |
| Permitted trailer load with brakes (12%) | 1400 kg (3086.47 lbs.) |
| Permitted trailer load without brakes | 695 kg (1532.21 lbs.) |
| Permitted towbar download | 75 kg (165.35 lbs.) |
| Length | 4640 mm (182.68 in.) |
| Width | 1825 mm (71.85 in.) |
| Height | 1377 mm (54.21 in.) |
| Wheelbase | 2810 mm (110.63 in.) |
| Front track | 1547 mm (60.91 in.) |
| Rear (Back) track | 1593 mm (62.72 in.) |
| Ride height (ground clearance) | 130 mm (5.12 in.) |
| Drag coefficient (Cd) | 0.29 |
| Minimum turning circle (turning diameter) | 11.3 m (37.07 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 | 6 gears, manual transmission |
| Front suspension | Independent coil spring |
| Rear suspension | Independent multi-link suspension |
| 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 | 225/50 R17; 225/45 R18; 255/40 R18; 225/40 R19; 255/35 R19 |
| Wheel rims size | 7.5J x 17; 8J x 18; 8.5J x 18; 8J x 19; 8.5J x 19 |
INTRODUCTION
The BMW 420i Coupe (F32, facelift 2017) served as the entry-level model within the 4 Series range. Introduced after the mid-cycle refresh in 2017, it combined the sleek styling of the 4 Series with a more economical and accessible powertrain. The facelift brought subtle but noticeable changes to the exterior, including revised headlights and taillights, along with interior enhancements. This variant aimed to broaden the appeal of the 4 Series, attracting buyers who prioritized efficiency and affordability without sacrificing the core BMW driving experience. It competed with other premium compact coupes like the Audi A5 Coupe and Mercedes-Benz C-Class Coupe.
Powertrain & Engine Architecture
At the heart of the 420i lies the BMW B48B20A 2.0-liter turbocharged inline-four cylinder engine. This engine is a member of BMW’s modular engine family, known for its efficiency and responsiveness. The B48 utilizes direct fuel injection, operating at a compression ratio of 11:1, and is equipped with a twin-scroll turbocharger and intercooler to maximize power output and minimize turbo lag. The engine produces 184 horsepower at 5000 rpm and 290 Nm (213.89 lb-ft) of torque between 1350 and 4600 rpm. The 420i was exclusively offered with a 6-speed manual transmission, providing a traditional driving experience. The engine’s longitudinal mounting and rear-wheel-drive configuration contribute to the car’s balanced handling characteristics.
Driving Characteristics
The 420i, with its 184 hp and 6-speed manual transmission, delivers a respectable, though not overwhelming, driving experience. Acceleration from 0 to 60 mph takes approximately 6.9 seconds. While not as quick as the 430i or 440i, the 420i offers sufficient power for everyday driving and spirited backroad excursions. The engine’s torque curve provides good low-end responsiveness, making it easy to navigate city streets. The 6-speed manual transmission is well-matched to the engine’s characteristics, offering precise shifts and a satisfying engagement. Compared to the automatic transmissions available in other 4 Series models, the manual gearbox provides a more direct connection between driver and machine. The rear-wheel-drive layout contributes to the car’s balanced handling and allows for a degree of oversteer when pushed.
Equipment & Trim Levels
The 420i Coupe came standard with a comprehensive list of features, including automatic climate control, power-adjustable front seats, a BMW iDrive infotainment system with a 6.5-inch display screen, and a suite of safety features like ABS, stability control, and airbags. Upholstery typically consisted of cloth or leatherette, with optional leather upgrades available. Common optional extras included a larger iDrive display screen, navigation system, premium sound system, sunroof, and parking sensors. The interior design was characterized by BMW’s signature driver-focused layout, with a slightly angled center console and high-quality materials. Trim levels were relatively simple, with most customization options available as individual add-ons.
Chassis & Braking
The 420i Coupe utilizes a sophisticated chassis design featuring an independent coil spring suspension at the front and an independent multi-link suspension at the rear. This setup provides a comfortable ride while maintaining excellent handling characteristics. The car is equipped with ventilated disc brakes on all four wheels, providing ample stopping power. ABS (Anti-lock Braking System) is standard, enhancing safety and control during emergency braking situations. The steering system is a rack-and-pinion type with electric power assistance, offering precise and responsive steering feel. The relatively lower weight of the 420i compared to its more powerful siblings contributes to its agility and responsiveness.
Market Reception & Comparison
The 420i Coupe was generally well-received by automotive critics, who praised its stylish design, comfortable ride, and engaging driving dynamics. However, some reviewers noted that the engine’s performance was adequate but not exceptional. Compared to the 430i and 440i, the 420i offered a more affordable entry point into the 4 Series range, but at the expense of outright performance. Fuel economy was a strong point, with the 420i achieving combined fuel consumption figures of around 38-40 mpg. In terms of reliability, the B48 engine has proven to be generally robust, although some owners have reported issues with oil leaks and cooling system components.
Legacy
The BMW 420i Coupe (F32, facelift 2017) remains a popular choice in the used car market, offering a compelling combination of style, performance, and affordability. The B48 engine has established a reputation for reliability, making the 420i a relatively low-risk purchase. While not as sought-after as the higher-performance 4 Series variants, the 420i appeals to buyers who prioritize fuel efficiency and a comfortable driving experience. Its classic coupe styling and BMW badge continue to attract enthusiasts, ensuring its place as a desirable entry-level premium vehicle.
