Car comparison

BMW 4 Series Gran Coupe (F36) 420ivsBMW 4 Series Convertible (G23) 420d

Compare specs, acceleration, fuel consumption, dimensions, practicality, and estimated running costs side by side.

New comparison

BMW 4 Series Gran Coupe (F36)

420i

184 hp1997 ccGasolineRWDManualTurbochargedCoupe2014-2016

BMW 4 Series Convertible (G23)

420d

190 hp1995 ccDieselRWDAutomaticTurbochargedCabriolet / convertible2020-2024

Comparison overview

Use the estimates as comparison hints and verify exact figures before making decisions.

BMW 4 Series Convertible (G23) 420d

Most powerful
190 hp
142 kW
Highest torque
400 Nm
295 lb-ft
Lowest combined fuel consumption
4.5 L/100 km
52.3 mpg US
62.8 mpg UK
Lowest city consumption
5.0 L/100 km
47.0 mpg US
56.5 mpg UK
Lowest highway consumption
4.3 L/100 km
54.7 mpg US
65.7 mpg UK
Best estimated range
1,311 km
815 mi
Best performance score
52/100
Best economy score
95/100

BMW 4 Series Gran Coupe (F36) 420i

Quickest 0-100 km/h
7.5 s
Fastest top speed
236 km/h
147 mph
Lightest
1,555 kg
3,428 lb
Best power-to-weight
118 hp/t
88 kW/t
8.5 kg/hp
Best overall score
56/100
Best practicality score
70/100

Specification comparison

Specification comparison
Model	BMW4 Series Gran Coupe (F36)420i	BMW4 Series Convertible (G23)420d
Power	184hp137kW	190hp142kW
Torque	270Nm199lb-ft	400Nm295lb-ft
Curb weight	1,555kg3,428lb	1,775kg3,913lb
Gross weight	2,040kg4,497lb	2,270kg5,004lb
Top speed	236 km/h 147 mph	236 km/h 147 mph
To 99% top speed	95.9s99% target: 234 km/h / 145 mph Calculated	99.3s99% target: 234 km/h / 145 mph Calculated
0-100 km/h	7.5s	7.6s
0-200 km/h	32.7s Calculated	33.6s Calculated
0-60 mph	7.1s Calculated	7.2s Calculated
Fuel consumption	6.6L/100 km35.6mpg US42.8mpg UK	4.5L/100 km52.3mpg US62.8mpg UK
Fuel consumption city	8.9L/100 km26.4mpg US31.7mpg UK	5L/100 km47mpg US56.5mpg UK
Fuel consumption highway	5.2L/100 km45.2mpg US54.3mpg UK	4.3L/100 km54.7mpg US65.7mpg UK
Quarter mile	15.4s Calculated	15.5s Calculated
Power-to-weight	118hp/t88kW/t54hp/1000 lb Calculated	107hp/t80kW/t49hp/1000 lb Calculated
Torque-to-weight	174Nm/t116lb-ft/ton Calculated	225Nm/t151lb-ft/ton Calculated
Estimated range	909km565mi Calculated	1,311km815mi Calculated
Displacement	1,997cc122cu in	1,995cc122cu in
Length	4,638mm183in	4,768mm188in
Width	1,825mm72in	1,852mm73in
Height	1,389mm55in	1,384mm54in
Wheelbase	2,810mm111in	2,851mm112in
Front track	1,557mm61in	1,575mm62in
Rear track	1,605mm63in	1,611mm63in
Ground clearance	-	124mm5in
Trunk volume	-	300L
Max trunk volume	-	385L
Doors	5	2
Seats	5	4
Fuel tank	60L	59L
CO2 emissions	153g/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 Gran Coupe (F36) 420iBMW 4 Series Convertible (G23) 420dPowerTorque

Dyno simulation data table
Vehicle	Peak power RPM	Peak torque RPM	Max engine speed
BMW4 Series Gran Coupe (F36)420i	5,000-6,250 rpm	1,250-4,500 rpm	6,500 rpm
BMW4 Series Convertible (G23)420d	4,000 rpm	1,750-2,500 rpm	4,250 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
Metric	BMW4 Series Gran Coupe (F36)420i	BMW4 Series Convertible (G23)420d
	Acceleration checkpoints
0-60 mph 0-97 km/h	7.1 s	7.2 s
0-100 km/h 0-62 mph	7.5 s	7.6 s
0-200 km/h 0-124 mph	32.7 s	33.6 s
Top speed	236 km/h 147 mph	236 km/h 147 mph
	Drag race simulation
60 ft 18 m	2.5 s	2.5 s
330 ft 101 m	6.7 s	6.7 s
1/8 mile 201 m	10.0 s	10.1 s
1000 ft 305 m	13.0 s	13.0 s
1/4 mile 402 m	15.4 s	15.5 s
Trap speed 1/4 mile 402 m	149 km/h 93 mph	148 km/h 92 mph

Power comparison

Bar comparison chart for Power. Higher is better · hp / kW

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	184 hp 137 kW
BMW4 Series Convertible (G23)420d	190 hp 142 kW

BMW 4 Series Convertible (G23) 420d has 6 hp more than BMW 4 Series Gran Coupe (F36) 420i.

The biggest power difference is between BMW 4 Series Gran Coupe (F36) 420i and BMW 4 Series Convertible (G23) 420d: 6 hp (4 kW).

Torque comparison

Bar comparison chart for Torque. Higher is better · Nm / lb-ft

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	270 Nm 199 lb-ft
BMW4 Series Convertible (G23)420d	400 Nm 295 lb-ft

Curb weight comparison

Bar comparison chart for Curb weight. Lower is better · kg / lb

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	1,555 kg 3,428 lb
BMW4 Series Convertible (G23)420d	1,775 kg 3,913 lb

Top speed without limiter comparison

Bar comparison chart for Top speed without limiter. Higher is better · km/h / mph

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	236 km/h 147 mph
BMW4 Series Convertible (G23)420d	236 km/h 147 mph

0-100 km/h comparison

Bar comparison chart for 0-100 km/h. Lower is better · seconds

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	7.5 s
BMW4 Series Convertible (G23)420d	7.6 s

Although BMW 4 Series Convertible (G23) 420d has more power, BMW 4 Series Gran Coupe (F36) 420i is quicker from 0-100 km/h.

The biggest 0-100 km/h difference is between BMW 4 Series Gran Coupe (F36) 420i and BMW 4 Series Convertible (G23) 420d: 0.1 s.

Fuel consumption comparison

Bar comparison chart for Fuel consumption. Lower is better · L/100 km / mpg US / mpg UK

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	6.6 L/100 km 35.6 mpg US 42.8 mpg UK
BMW4 Series Convertible (G23)420d	4.5 L/100 km 52.3 mpg US 62.8 mpg UK

The biggest fuel consumption difference is between BMW 4 Series Convertible (G23) 420d and BMW 4 Series Gran Coupe (F36) 420i: 2.1 L/100 km.

Power-to-weight comparison

Bar comparison chart for Power-to-weight. Higher is better · hp/t / kW/t

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	118 hp/t 88 kW/t 8.5 kg/hp
BMW4 Series Convertible (G23)420d	107 hp/t 80 kW/t 9.3 kg/hp

Estimated range comparison

Bar comparison chart for Estimated range. Higher is better · km / mi

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	909 km 565 mi
BMW4 Series Convertible (G23)420d	1,311 km 815 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
Vehicle	Power	Acceleration	Top speed
BMW4 Series Gran Coupe (F36)420i	184 hp 137 kW	7.5 s	236 km/h 147 mph
BMW4 Series Convertible (G23)420d	190 hp 142 kW	7.6 s	236 km/h 147 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 Gran Coupe (F36)420i

Power	184 hp 137 kW
0-100 km/h	7.5 s
Top speed 236 km/h 147 mph

Doors/seats	5 doors 5 seats
Trunk	-
Length	4,638 mm 182.6 in
Height	1,389 mm 54.7 in

BMW4 Series Convertible (G23)420d

Power	190 hp 142 kW
0-100 km/h	7.6 s
Top speed 236 km/h 147 mph

Doors/seats	2 doors 4 seats
Trunk	300 L 10.6 cu ft
Length	4,768 mm 187.7 in
Height	1,384 mm 54.5 in

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 Gran Coupe (F36)420i

Power	184 hp 137 kW
0-100 km/h	7.5 s
Top speed 236 km/h 147 mph

6.6 L/100 km

35.6 mpg US

42.8 mpg UK

BMW4 Series Convertible (G23)420d

Power	190 hp 142 kW
0-100 km/h	7.6 s
Top speed 236 km/h 147 mph

4.5 L/100 km

52.3 mpg US

62.8 mpg UK

BMW 4 Series Convertible (G23) 420d 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.

Acceleration vs fuel consumption data table
Vehicle	Fuel consumption, L/100 km	0-100 km/h, s
BMW4 Series Gran Coupe (F36)420i	6.6 L/100 km 35.6 mpg US 42.8 mpg UK	7.5 s
BMW4 Series Convertible (G23)420d	4.5 L/100 km 52.3 mpg US 62.8 mpg UK	7.6 s

Power-to-weight vs fuel consumption

The shaded area favors higher power-to-weight with lower combined fuel consumption.

Power-to-weight vs fuel consumption data table
Vehicle	Power-to-weight, hp/t	Fuel consumption, L/100 km
BMW4 Series Gran Coupe (F36)420i	118 hp/t 88 kW/t 8.5 kg/hp	6.6 L/100 km 35.6 mpg US 42.8 mpg UK
BMW4 Series Convertible (G23)420d	107 hp/t 80 kW/t 9.3 kg/hp	4.5 L/100 km 52.3 mpg US 62.8 mpg UK

Detailed score breakdown

Vehicle

BMW4 Series Gran Coupe (F36)420i

BMW4 Series Convertible (G23)420d

Power

184 hp

137 kW

190 hp

142 kW

Torque

270 Nm

199 lb-ft

400 Nm

295 lb-ft

Acceleration

7.5 s

7.6 s

Top speed

236 km/h

147 mph

236 km/h

147 mph

Lightness

1,555 kg

3,428 lb

1,775 kg

3,913 lb

Fuel consumption

6.6 L/100 km

35.6 mpg US

42.8 mpg UK

4.5 L/100 km

52.3 mpg US

62.8 mpg UK

Practicality

Doors/seats	5 doors 5 seats
Trunk	-
Length	4,638 mm 182.6 in
Height	1,389 mm 54.7 in

Doors/seats	2 doors 4 seats
Trunk	300 L 10.6 cu ft
Length	4,768 mm 187.7 in
Height	1,384 mm 54.5 in

Range score

909 km

565 mi

1,311 km

815 mi

CO2 score

153 g/km

Trunk score

300 L

10.6 cu ft

Power-to-weight score

118 hp/t

88 kW/t

8.5 kg/hp

107 hp/t

80 kW/t

9.3 kg/hp

Overall

Fixed score

Fuel cost and annual usage

Estimate running costs from combined consumption, your annual distance, and the fuel price in your local currency.

Average annual distanceDistance unitFuel price in your local currencyPrice unit

Enter the fuel price in your local currency, for example €/L, $/gal, £/L or any other local currency.

LC = Local Currency

Fuel cost and annual usage
Vehicle	BMW 4 Series Gran Coupe (F36) 420i	BMW 4 Series Convertible (G23) 420d
Consumption	6.6 L/100 km35.6 mpg US42.8 mpg UK	4.5 L/100 km52.3 mpg US62.8 mpg UK
Cost / 100 km	11.55 LC100 km	7.88 LC100 km
Cost / 100 mi	18.59 LC100 mi	12.67 LC100 mi
Annual fuel used	990 L262 US gal218 UK gal	675 L178 US gal148 UK gal
Annual fuel cost	1,733 LC/year	1,181 LC/year