BMW 4 Series Convertible (G23)
Car comparison
BMW 4 Series Convertible (G23) 420ivsBMW 4 Series Coupe (F32) · Facelift 2017 420i
Compare specs, acceleration, fuel consumption, dimensions, practicality, and estimated running costs side by side.
New comparisonBMW 4 Series Coupe (F32) · Facelift 2017
420i
Comparison overview
Use the estimates as comparison hints and verify exact figures before making decisions.
Best choices
BMW 4 Series Convertible (G23) 420i
- Fastest top speed236 km/h147 mph
- Most powerful184 hp137 kW
- Highest torque300 Nm221 lb-ft
- Lowest combined fuel consumption6.1 L/100 km38.6 mpg US46.3 mpg UK
- Lowest city consumption7.4 L/100 km31.8 mpg US38.2 mpg UK
- Lowest highway consumption5.4 L/100 km43.6 mpg US52.3 mpg UK
- Best estimated range967 km601 mi
- Best economy score90/100
BMW 4 Series Coupe (F32) Facelift 2017 420i
- Quickest 0-100 km/h7.6 s
- Lightest1,560 kg3,439 lb
- Best power-to-weight118 hp/t88 kW/t8.5 kg/hp
- Largest trunk445 L
- Best overall score50/100
- Best performance score49/100
- Best practicality score53/100
Specification comparison
| Model | BMW4 Series Convertible (G23)420i | BMW4 Series Coupe (F32)Facelift 2017420i |
|---|---|---|
| Power | 184hp137kW | 184hp137kW |
| Torque | 300Nm221lb-ft | 270Nm199lb-ft |
| Curb weight | 1,690kg3,726lb | 1,560kg3,439lb |
| Gross weight | 2,185kg4,817lb | 2,080kg4,586lb |
| Top speed | 236 km/h 147 mph | 233 km/h 145 mph |
| To 99% top speed | 107.5s99% target: 234 km/h / 145 mph Calculated | 96.7s99% target: 231 km/h / 143 mph Calculated |
| 0-100 km/h | 8.2s | 7.6s |
| 0-200 km/h | 36.3s Calculated | 34.4s Calculated |
| 0-60 mph | 7.8s Calculated | 7.2s Calculated |
| Fuel consumption | 6.1L/100 km38.6mpg US46.3mpg UK | 6.9L/100 km34.1mpg US40.9mpg UK |
| Fuel consumption city | 7.4L/100 km31.8mpg US38.2mpg UK | 9L/100 km26.1mpg US31.4mpg UK |
| Fuel consumption highway | 5.4L/100 km43.6mpg US52.3mpg UK | 5.7L/100 km41.3mpg US49.6mpg UK |
| Quarter mile | 15.9s Calculated | 15.5s Calculated |
| Power-to-weight | 109hp/t81kW/t49hp/1000 lb Calculated | 118hp/t88kW/t54hp/1000 lb Calculated |
| Torque-to-weight | 178Nm/t119lb-ft/ton Calculated | 173Nm/t116lb-ft/ton Calculated |
| Estimated range | 967km601mi Calculated | 870km540mi Calculated |
| Displacement | 1,998cc122cu in | 1,998cc122cu in |
| Length | 4,768mm188in | 4,640mm183in |
| Width | 1,852mm73in | 1,825mm72in |
| Height | 1,384mm54in | 1,392mm55in |
| Wheelbase | 2,851mm112in | 2,810mm111in |
| Front track | 1,575mm62in | 1,543mm61in |
| Rear track | 1,611mm63in | 1,589mm63in |
| Ground clearance | 124mm5in | - |
| Trunk volume | 300L | 445L |
| Max trunk volume | 385L | - |
| Doors | 2 | 2 |
| Seats | 4 | 4 |
| Fuel tank | 59L | 60L |
| CO2 emissions | - | 161g/km |
Performance charts
Use the estimates as comparison hints and verify exact figures before making decisions.
Dyno simulation
Estimated stock-style power and torque curves by engine speed.
- BMW 4 Series Convertible (G23) 420i: Power / Torque
- BMW 4 Series Coupe (F32) Facelift 2017 420i: Power / Torque
| Vehicle | Peak power RPM | Peak torque RPM | Max engine speed |
|---|---|---|---|
| BMW4 Series Convertible (G23)420i | 5,000-6,500 rpm | 1,350-4,000 rpm | 6,750 rpm |
| BMW4 Series Coupe (F32)Facelift 2017420i | 5,000 rpm | 1,350-4,600 rpm | 5,250 rpm |
Acceleration curve
Estimated speed over time for selected vehicles.
| Metric | BMW4 Series Convertible (G23)420i | BMW4 Series Coupe (F32)Facelift 2017420i |
|---|---|---|
| Acceleration checkpoints | ||
0-60 mph 0-97 km/h | 7.8 s | 7.2 s |
0-100 km/h 0-62 mph | 8.2 s | 7.6 s |
0-200 km/h 0-124 mph | 36.3 s | 34.4 s |
| Top speed | 236 km/h 147 mph | 233 km/h 145 mph |
| Drag race simulation | ||
60 ft 18 m | 2.6 s | 2.5 s |
330 ft 101 m | 6.9 s | 6.7 s |
1/8 mile 201 m | 10.4 s | 10.1 s |
1000 ft 305 m | 13.4 s | 13.0 s |
1/4 mile 402 m | 15.9 s | 15.5 s |
Trap speed 1/4 mile 402 m | 145 km/h 90 mph | 148 km/h 92 mph |
Power comparison
Bar comparison chart for Power. Higher is better · hp / kW
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 184 hp 137 kW |
| BMW4 Series Coupe (F32)Facelift 2017420i | 184 hp 137 kW |
Torque comparison
Bar comparison chart for Torque. Higher is better · Nm / lb-ft
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 300 Nm 221 lb-ft |
| BMW4 Series Coupe (F32)Facelift 2017420i | 270 Nm 199 lb-ft |
Curb weight comparison
Bar comparison chart for Curb weight. Lower is better · kg / lb
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 1,690 kg 3,726 lb |
| BMW4 Series Coupe (F32)Facelift 2017420i | 1,560 kg 3,439 lb |
Top speed without limiter comparison
Bar comparison chart for Top speed without limiter. Higher is better · km/h / mph
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 236 km/h 147 mph |
| BMW4 Series Coupe (F32)Facelift 2017420i | 233 km/h 145 mph |
0-100 km/h comparison
Bar comparison chart for 0-100 km/h. Lower is better · seconds
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 8.2 s |
| BMW4 Series Coupe (F32)Facelift 2017420i | 7.6 s |
The biggest 0-100 km/h difference is between BMW 4 Series Coupe (F32) Facelift 2017 420i and BMW 4 Series Convertible (G23) 420i: 0.6 s.
Fuel consumption comparison
Bar comparison chart for Fuel consumption. Lower is better · L/100 km / mpg US / mpg UK
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 6.1 L/100 km 38.6 mpg US 46.3 mpg UK |
| BMW4 Series Coupe (F32)Facelift 2017420i | 6.9 L/100 km 34.1 mpg US 40.9 mpg UK |
The biggest fuel consumption difference is between BMW 4 Series Convertible (G23) 420i and BMW 4 Series Coupe (F32) Facelift 2017 420i: 0.8 L/100 km.
Power-to-weight comparison
Bar comparison chart for Power-to-weight. Higher is better · hp/t / kW/t
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 109 hp/t 81 kW/t 9.2 kg/hp |
| BMW4 Series Coupe (F32)Facelift 2017420i | 118 hp/t 88 kW/t 8.5 kg/hp |
Estimated range comparison
Bar comparison chart for Estimated range. Higher is better · km / mi
| Vehicle | Value |
|---|---|
| BMW4 Series Convertible (G23)420i | 967 km 601 mi |
| BMW4 Series Coupe (F32)Facelift 2017420i | 870 km 540 mi |
Performance spider chart
Radar chart comparing normalized performance and fuel-consumption scores.
| Vehicle | Power | Acceleration | Top speed |
|---|---|---|---|
| BMW4 Series Convertible (G23)420i | 184 hp 137 kW | 8.2 s | 236 km/h 147 mph |
| BMW4 Series Coupe (F32)Facelift 2017420i | 184 hp 137 kW | 7.6 s | 233 km/h 145 mph |
Most attractive quadrant
Scatter chart with performance score on the X axis and practicality score on the Y axis.
| Vehicle | Performance score | Practicality score | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| BMW4 Series Convertible (G23)420i |
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| BMW4 Series Coupe (F32)Facelift 2017420i |
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Performance vs fuel economy
Cars closer to the top-right corner combine stronger performance with better fuel economy scores.
| Vehicle | Performance score | Fuel economy score | ||||||
|---|---|---|---|---|---|---|---|---|
| BMW4 Series Convertible (G23)420i |
| 6.1 L/100 km 38.6 mpg US 46.3 mpg UK | ||||||
| BMW4 Series Coupe (F32)Facelift 2017420i |
| 6.9 L/100 km 34.1 mpg US 40.9 mpg UK | ||||||
BMW 4 Series Coupe (F32) Facelift 2017 420i is closest to the top-right balance target for performance and fuel economy.
Acceleration vs fuel consumption
Cars closer to the lower-left corner offer a better mix of quick acceleration and low fuel consumption.
| Vehicle | Fuel consumption, L/100 km | 0-100 km/h, s |
|---|---|---|
| BMW4 Series Convertible (G23)420i | 6.1 L/100 km 38.6 mpg US 46.3 mpg UK | 8.2 s |
| BMW4 Series Coupe (F32)Facelift 2017420i | 6.9 L/100 km 34.1 mpg US 40.9 mpg UK | 7.6 s |
Power-to-weight vs fuel consumption
The shaded area favors higher power-to-weight with lower combined fuel consumption.
| Vehicle | Power-to-weight, hp/t | Fuel consumption, L/100 km |
|---|---|---|
| BMW4 Series Convertible (G23)420i | 109 hp/t 81 kW/t 9.2 kg/hp | 6.1 L/100 km 38.6 mpg US 46.3 mpg UK |
| BMW4 Series Coupe (F32)Facelift 2017420i | 118 hp/t 88 kW/t 8.5 kg/hp | 6.9 L/100 km 34.1 mpg US 40.9 mpg UK |
Detailed score breakdown
| Vehicle | BMW4 Series Convertible (G23)420i | BMW4 Series Coupe (F32)Facelift 2017420i | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Power | 184 hp 137 kW | 184 hp 137 kW | ||||||||||||||||
| Torque | 300 Nm 221 lb-ft | 270 Nm 199 lb-ft | ||||||||||||||||
| Acceleration | 8.2 s | 7.6 s | ||||||||||||||||
| Top speed | 236 km/h 147 mph | 233 km/h 145 mph | ||||||||||||||||
| Lightness | 1,690 kg 3,726 lb | 1,560 kg 3,439 lb | ||||||||||||||||
| Fuel consumption | 6.1 L/100 km 38.6 mpg US 46.3 mpg UK | 6.9 L/100 km 34.1 mpg US 40.9 mpg UK | ||||||||||||||||
| Practicality |
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| Range score | 967 km 601 mi | 870 km 540 mi | ||||||||||||||||
| CO2 score | - | 161 g/km | ||||||||||||||||
| Trunk score | 300 L 10.6 cu ft | 445 L 15.7 cu ft | ||||||||||||||||
| Power-to-weight score | 109 hp/t 81 kW/t 9.2 kg/hp | 118 hp/t 88 kW/t 8.5 kg/hp | ||||||||||||||||
| Overall | Fixed score | Fixed score |
Fuel cost and annual usage
Estimate running costs from combined consumption, your annual distance, and the fuel price in your local currency.
Enter the fuel price in your local currency, for example €/L, $/gal, £/L or any other local currency.
LC = Local Currency
| Vehicle | BMW 4 Series Convertible (G23) 420i | BMW 4 Series Coupe (F32) Facelift 2017 420i |
|---|---|---|
| Consumption | 6.1 L/100 km38.6 mpg US46.3 mpg UK | 6.9 L/100 km34.1 mpg US40.9 mpg UK |
| Cost / 100 km | 10.67 LC100 km | 12.08 LC100 km |
| Cost / 100 mi | 17.18 LC100 mi | 19.43 LC100 mi |
| Annual fuel used | 915 L242 US gal201 UK gal | 1,035 L273 US gal228 UK gal |
| Annual fuel cost | 1,601 LC/year | 1,811 LC/year |
Head-to-head comparisons
BMW 4 Series Convertible (G23) 420i
- Has 30 Nm more
- Has 3 km/h (2 mph) higher top speed
- Uses 0.8 L/100 km less fuel
- Has 98 km (61 mi) more estimated range
Pros
- Highest top speed
- Most powerful
- Highest torque
- Lowest combined fuel consumption
- Best estimated range
Cons
- Slowest 0-100 km/h
- Heaviest
- Smallest trunk
BMW 4 Series Coupe (F32) Facelift 2017 420i
- Is 130 kg lighter
- Is 0.6 s quicker from 0-100 km/h
- Has 9 hp/t better power-to-weight
- Has 145 L more trunk volume
Pros
- Quickest 0-100 km/h in this comparison
- Lightest
- Best power-to-weight ratio
- Largest trunk
Cons
- Highest combined fuel consumption
- Lowest top speed
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