Car comparison

BMW 8 Series (G15) 840ivsBMW X4 (G02) M40i

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

New comparison

BMW 8 Series (G15)

840i

340 hp2998 ccGasolineRWDAutomaticTurbochargedCoupe2019-2020
VS

BMW X4 (G02)

M40i

360 hp2998 ccGasolineAWDAutomaticTurbocharged2019-2021

Comparison overview

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

Best choices

BMW 8 Series (G15) 840i

  • Fastest top speed
    265 km/h
    165 mph Unrestricted
    250 km/h
    155 mph Restricted
  • Highest torque
    500 Nm
    369 lb-ft
  • Lightest
    1,710 kg
    3,770 lb
  • Best power-to-weight
    199 hp/t
    148 kW/t
    5.0 kg/hp
  • Lowest combined fuel consumption
    7.3 L/100 km
    32.2 mpg US
    38.7 mpg UK
  • Lowest city consumption
    9.0 L/100 km
    26.1 mpg US
    31.4 mpg UK
  • Lowest highway consumption
    6.3 L/100 km
    37.3 mpg US
    44.8 mpg UK
  • Best estimated range
    932 km
    579 mi
  • Best performance score
    71/100
  • Best economy score
    87/100

BMW X4 (G02) M40i

  • Quickest 0-100 km/h
    4.8 s
  • Most powerful
    360 hp
    268 kW
  • Largest trunk
    525 L
  • Best overall score
    73/100
  • Best practicality score
    76/100

Specification comparison

Specification comparison
ModelBMW8 Series (G15)840iBMWX4 (G02)M40i
Power
340hp254kW
360hp268kW
Torque
500Nm369lb-ft
500Nm369lb-ft
Curb weight
1,710kg3,770lb
1,865kg4,112lb
Gross weight
2,225kg4,905lb
2,430kg5,357lb
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Calculated
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Calculated
To 99% top speed
69.0s99% target: 262 km/h / 163 mph
Calculated
70.3s99% target: 257 km/h / 160 mph
Calculated
0-100 km/h
5.0s
4.8s
0-200 km/h
17.5s
Calculated
18.0s
Calculated
0-60 mph
4.8s
Calculated
4.6s
Calculated
Fuel consumption
7.3L/100 km32.2mpg US38.7mpg UK
8.1L/100 km29mpg US34.9mpg UK
Fuel consumption city
9L/100 km26.1mpg US31.4mpg UK
10L/100 km23.5mpg US28.2mpg UK
Fuel consumption highway
6.3L/100 km37.3mpg US44.8mpg UK
7L/100 km33.6mpg US40.4mpg UK
Quarter mile
13.1s
Calculated
13.0s
Calculated
Power-to-weight
199hp/t148kW/t90hp/1000 lb
Calculated
193hp/t144kW/t88hp/1000 lb
Calculated
Torque-to-weight
292Nm/t196lb-ft/ton
Calculated
268Nm/t179lb-ft/ton
Calculated
Estimated range
932km579mi
Calculated
802km499mi
Calculated
Displacement
2,998cc183cu in
2,998cc183cu in
Length
4,843mm191in
4,752mm187in
Width
1,902mm75in
1,938mm76in
Height
1,341mm53in
1,621mm64in
Wheelbase
2,822mm111in
2,864mm113in
Front track
1,627mm64in
-
Rear track
1,642mm65in
-
Ground clearance
121mm5in
-
Trunk volume
420L
525L
Max trunk volume-
1,430L
Doors
2
5
Seats
4
5
Fuel tank
68L
65L
CO2 emissions-
185g/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 8 Series (G15) 840iBMW X4 (G02) M40iPowerTorque
  • BMW 8 Series (G15) 840i: Power / Torque
  • BMW X4 (G02) M40i: Power / Torque
Dyno simulation data table
VehiclePeak power RPMPeak torque RPMMax engine speed
BMW8 Series (G15)840i5,000-6,500 rpm1,600-4,500 rpm6,750 rpm
BMWX4 (G02)M40i5,200-6,500 rpm1,850-5,000 rpm6,750 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
MetricBMW8 Series (G15)840iBMWX4 (G02)M40i
Acceleration checkpoints
0-60 mph
0-97 km/h
4.8 s
4.6 s
0-100 km/h
0-62 mph
5.0 s
4.8 s
0-200 km/h
0-124 mph
17.5 s
18.0 s
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Likely limited
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Likely limited
Drag race simulation
60 ft
18 m
2.2 s
2.1 s
330 ft
101 m
5.7 s
5.6 s
1/8 mile
201 m
8.6 s
8.4 s
1000 ft
305 m
11.1 s
10.9 s
1/4 mile
402 m
13.1 s
13.0 s
Trap speed
1/4 mile
402 m
176 km/h
109 mph
175 km/h
109 mph

Power comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
340 hp
254 kW
BMWX4 (G02)M40i
360 hp
268 kW

BMW X4 (G02) M40i has 20 hp more than BMW 8 Series (G15) 840i.

The biggest power difference is between BMW 8 Series (G15) 840i and BMW X4 (G02) M40i: 20 hp (15 kW).

Torque comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
500 Nm
369 lb-ft
BMWX4 (G02)M40i
500 Nm
369 lb-ft

Curb weight comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
1,710 kg
3,770 lb
BMWX4 (G02)M40i
1,865 kg
4,112 lb

Top speed without limiter comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
BMWX4 (G02)M40i
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph

0-100 km/h comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i5.0 s
BMWX4 (G02)M40i4.8 s

The biggest 0-100 km/h difference is between BMW X4 (G02) M40i and BMW 8 Series (G15) 840i: 0.2 s.

Fuel consumption comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
7.3 L/100 km
32.2 mpg US
38.7 mpg UK
BMWX4 (G02)M40i
8.1 L/100 km
29.0 mpg US
34.9 mpg UK

The biggest fuel consumption difference is between BMW 8 Series (G15) 840i and BMW X4 (G02) M40i: 0.8 L/100 km.

Power-to-weight comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
199 hp/t
148 kW/t
5.0 kg/hp
BMWX4 (G02)M40i
193 hp/t
144 kW/t
5.2 kg/hp

Estimated range comparison

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

Chart data table
VehicleValue
BMW8 Series (G15)840i
932 km
579 mi
BMWX4 (G02)M40i
802 km
499 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
VehiclePowerAccelerationTop speed
BMW8 Series (G15)840i
340 hp
254 kW
5.0 s
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
BMWX4 (G02)M40i
360 hp
268 kW
4.8 s
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph

Most attractive quadrant

Scatter chart with performance score on the X axis and practicality score on the Y axis.

Chart data table
VehiclePerformance scorePracticality score
BMW8 Series (G15)840i
Power
340 hp
254 kW
0-100 km/h5.0 s
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Doors/seats
2 doors
4 seats
Trunk
420 L
14.8 cu ft
Length
4,843 mm
190.7 in
Height
1,341 mm
52.8 in
BMWX4 (G02)M40i
Power
360 hp
268 kW
0-100 km/h4.8 s
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Doors/seats
5 doors
5 seats
Trunk
525 L
18.5 cu ft
Length
4,752 mm
187.1 in
Height
1,621 mm
63.8 in

Performance vs fuel economy

Cars closer to the top-right corner combine stronger performance with better fuel economy scores.

Performance vs fuel economy data table
VehiclePerformance scoreFuel economy score
BMW8 Series (G15)840i
Power
340 hp
254 kW
0-100 km/h5.0 s
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
7.3 L/100 km
32.2 mpg US
38.7 mpg UK
BMWX4 (G02)M40i
Power
360 hp
268 kW
0-100 km/h4.8 s
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
8.1 L/100 km
29.0 mpg US
34.9 mpg UK

BMW 8 Series (G15) 840i 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
VehicleFuel consumption, L/100 km0-100 km/h, s
BMW8 Series (G15)840i
7.3 L/100 km
32.2 mpg US
38.7 mpg UK
5.0 s
BMWX4 (G02)M40i
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
4.8 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
VehiclePower-to-weight, hp/tFuel consumption, L/100 km
BMW8 Series (G15)840i
199 hp/t
148 kW/t
5.0 kg/hp
7.3 L/100 km
32.2 mpg US
38.7 mpg UK
BMWX4 (G02)M40i
193 hp/t
144 kW/t
5.2 kg/hp
8.1 L/100 km
29.0 mpg US
34.9 mpg UK

Detailed score breakdown

Detailed score breakdown
VehicleBMW8 Series (G15)840iBMWX4 (G02)M40i
Power
340 hp
254 kW
360 hp
268 kW
Torque
500 Nm
369 lb-ft
500 Nm
369 lb-ft
Acceleration
5.0 s
4.8 s
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Lightness
1,710 kg
3,770 lb
1,865 kg
4,112 lb
Fuel consumption
7.3 L/100 km
32.2 mpg US
38.7 mpg UK
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
Practicality
Doors/seats
2 doors
4 seats
Trunk
420 L
14.8 cu ft
Length
4,843 mm
190.7 in
Height
1,341 mm
52.8 in
Doors/seats
5 doors
5 seats
Trunk
525 L
18.5 cu ft
Length
4,752 mm
187.1 in
Height
1,621 mm
63.8 in
Range score
932 km
579 mi
802 km
499 mi
CO2 score
-
185 g/km
Trunk score
420 L
14.8 cu ft
525 L
18.5 cu ft
Power-to-weight score
199 hp/t
148 kW/t
5.0 kg/hp
193 hp/t
144 kW/t
5.2 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

Fuel cost and annual usage
VehicleBMW 8 Series (G15) 840iBMW X4 (G02) M40i
Consumption7.3 L/100 km32.2 mpg US38.7 mpg UK8.1 L/100 km29 mpg US34.9 mpg UK
Cost / 100 km12.78 LC100 km14.17 LC100 km
Cost / 100 mi20.56 LC100 mi22.81 LC100 mi
Annual fuel used1,095 L289 US gal241 UK gal1,215 L321 US gal267 UK gal
Annual fuel cost1,916 LC/year2,126 LC/year

Head-to-head comparisons

BMW 8 Series (G15) 840i

  • Is 155 kg lighter
  • Has 5 km/h (3 mph) higher top speed
  • Uses 0.8 L/100 km less fuel
  • Has 6 hp/t better power-to-weight
  • Has 129 km (80 mi) more estimated range

Pros

  • Highest top speed
  • Highest torque
  • Lightest
  • Lowest combined fuel consumption
  • Best power-to-weight ratio
  • Best estimated range

Cons

  • Slowest 0-100 km/h
  • Lowest power
  • Smallest trunk

BMW X4 (G02) M40i

  • Has 20 hp more
  • Is 0.2 s quicker from 0-100 km/h
  • Has 105 L more trunk volume

Pros

  • Quickest 0-100 km/h in this comparison
  • Most powerful
  • Largest trunk

Cons

  • Highest combined fuel consumption
  • Heaviest
  • Lowest top speed

Choose cars to compare

Brand
Model
Generation
Engine or modification
BMW 8 Series (G15) 840i
BMW X4 (G02) M40i
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BMW 8 Series (G15) 840i vs BMW X4 (G02) M40i - car comparison - FastVsFaster