Car comparison

BMW Z4 (E89) 30ivsBMW Z4 (G29) 20i

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

New comparison

BMW Z4 (E89)

30i

258 hp2996 ccGasolineRWDManualNaturally aspiratedRoadster2009-2011
VS

BMW Z4 (G29)

20i

197 hp1998 ccGasolineRWDManualTurbochargedRoadster2018-2022

Comparison overview

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

Best choices

BMW Z4 (G29) 20i

  • Highest torque
    320 Nm
    236 lb-ft
  • Lightest
    1,420 kg
    3,131 lb
  • Lowest combined fuel consumption
    6.9 L/100 km
    34.1 mpg US
    40.9 mpg UK
  • Lowest city consumption
    9.1 L/100 km
    25.8 mpg US
    31.0 mpg UK
  • Lowest highway consumption
    5.6 L/100 km
    42.0 mpg US
    50.4 mpg UK
  • Best estimated range
    754 km
    468 mi
  • Largest trunk
    281 L
  • Best economy score
    88/100
  • Best practicality score
    32/100

BMW Z4 (E89) 30i

  • Quickest 0-100 km/h
    5.8 s
  • Fastest top speed
    260 km/h
    162 mph Unrestricted
    250 km/h
    155 mph Restricted
  • Most powerful
    258 hp
    192 kW
  • Best power-to-weight
    173 hp/t
    129 kW/t
    5.8 kg/hp
  • Best overall score
    50/100
  • Best performance score
    61/100

Specification comparison

Specification comparison
ModelBMWZ4 (E89)30iBMWZ4 (G29)20i
Power
258hp192kW
197hp147kW
Torque
315Nm232lb-ft
320Nm236lb-ft
Curb weight
1,490kg3,285lb
1,420kg3,131lb
Gross weight
1,745kg3,847lb
1,725kg3,803lb
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Calculated
241 km/h
150 mph
To 99% top speed
76.0s99% target: 257 km/h / 160 mph
Calculated
80.6s99% target: 239 km/h / 148 mph
Calculated
0-100 km/h
5.8s
6.8s
0-200 km/h
20.5s
Calculated
26.9s
Calculated
0-60 mph
5.5s
Calculated
6.5s
Calculated
Fuel consumption
8.5L/100 km27.7mpg US33.2mpg UK
6.9L/100 km34.1mpg US40.9mpg UK
Fuel consumption city
12.4L/100 km19mpg US22.8mpg UK
9.1L/100 km25.8mpg US31.0mpg UK
Fuel consumption highway
6.2L/100 km37.9mpg US45.6mpg UK
5.6L/100 km42mpg US50.4mpg UK
Quarter mile
13.9s
Calculated
14.8s
Calculated
Power-to-weight
173hp/t129kW/t79hp/1000 lb
Calculated
139hp/t103kW/t63hp/1000 lb
Calculated
Torque-to-weight
211Nm/t141lb-ft/ton
Calculated
225Nm/t151lb-ft/ton
Calculated
Estimated range
647km402mi
Calculated
754km468mi
Calculated
Displacement
2,996cc183cu in
1,998cc122cu in
Length
4,239mm167in
4,324mm170in
Width
1,790mm70in
1,864mm73in
Height
1,291mm51in
1,304mm51in
Wheelbase
2,496mm98in
2,470mm97in
Front track
1,511mm59in
1,609mm63in
Rear track
1,537mm61in
1,616mm64in
Ground clearance-
117mm5in
Trunk volume
180L
281L
Max trunk volume
310L
-
Doors
2
2
Seats
2
2
Fuel tank
55L
52L

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 Z4 (E89) 30iBMW Z4 (G29) 20iPowerTorque
  • BMW Z4 (E89) 30i: Power / Torque
  • BMW Z4 (G29) 20i: Power / Torque
Dyno simulation data table
VehiclePeak power RPMPeak torque RPMMax engine speed
BMWZ4 (E89)30i6,600 rpm2,500 rpm6,850 rpm
BMWZ4 (G29)20i4,500-6,500 rpm1,450-4,200 rpm6,750 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
MetricBMWZ4 (E89)30iBMWZ4 (G29)20i
Acceleration checkpoints
0-60 mph
0-97 km/h
5.5 s
6.5 s
0-100 km/h
0-62 mph
5.8 s
6.8 s
0-200 km/h
0-124 mph
20.5 s
26.9 s
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Likely limited
241 km/h
150 mph
Drag race simulation
60 ft
18 m
2.3 s
2.5 s
330 ft
101 m
6.1 s
6.5 s
1/8 mile
201 m
9.1 s
9.7 s
1000 ft
305 m
11.7 s
12.5 s
1/4 mile
402 m
13.9 s
14.8 s
Trap speed
1/4 mile
402 m
168 km/h
105 mph
157 km/h
98 mph

Power comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i
258 hp
192 kW
BMWZ4 (G29)20i
197 hp
147 kW

BMW Z4 (E89) 30i has 61 hp more than BMW Z4 (G29) 20i.

The biggest power difference is between BMW Z4 (G29) 20i and BMW Z4 (E89) 30i: 61 hp (45 kW).

Torque comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i
315 Nm
232 lb-ft
BMWZ4 (G29)20i
320 Nm
236 lb-ft

Curb weight comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i
1,490 kg
3,285 lb
BMWZ4 (G29)20i
1,420 kg
3,131 lb

Top speed without limiter comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
BMWZ4 (G29)20i
241 km/h
150 mph

0-100 km/h comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i5.8 s
BMWZ4 (G29)20i6.8 s

The biggest 0-100 km/h difference is between BMW Z4 (E89) 30i and BMW Z4 (G29) 20i: 1.0 s.

Fuel consumption comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i
8.5 L/100 km
27.7 mpg US
33.2 mpg UK
BMWZ4 (G29)20i
6.9 L/100 km
34.1 mpg US
40.9 mpg UK

The biggest fuel consumption difference is between BMW Z4 (G29) 20i and BMW Z4 (E89) 30i: 1.6 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
BMWZ4 (E89)30i
173 hp/t
129 kW/t
5.8 kg/hp
BMWZ4 (G29)20i
139 hp/t
103 kW/t
7.2 kg/hp

Estimated range comparison

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

Chart data table
VehicleValue
BMWZ4 (E89)30i
647 km
402 mi
BMWZ4 (G29)20i
754 km
468 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
VehiclePowerAccelerationTop speed
BMWZ4 (E89)30i
258 hp
192 kW
5.8 s
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
BMWZ4 (G29)20i
197 hp
147 kW
6.8 s
241 km/h
150 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
BMWZ4 (E89)30i
Power
258 hp
192 kW
0-100 km/h5.8 s
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
Doors/seats
2 doors
2 seats
Trunk
180 L
6.4 cu ft
Length
4,239 mm
166.9 in
Height
1,291 mm
50.8 in
BMWZ4 (G29)20i
Power
197 hp
147 kW
0-100 km/h6.8 s
Top speed
241 km/h
150 mph
Doors/seats
2 doors
2 seats
Trunk
281 L
9.9 cu ft
Length
4,324 mm
170.2 in
Height
1,304 mm
51.3 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
BMWZ4 (E89)30i
Power
258 hp
192 kW
0-100 km/h5.8 s
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
8.5 L/100 km
27.7 mpg US
33.2 mpg UK
BMWZ4 (G29)20i
Power
197 hp
147 kW
0-100 km/h6.8 s
Top speed
241 km/h
150 mph
6.9 L/100 km
34.1 mpg US
40.9 mpg UK

BMW Z4 (E89) 30i 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
BMWZ4 (E89)30i
8.5 L/100 km
27.7 mpg US
33.2 mpg UK
5.8 s
BMWZ4 (G29)20i
6.9 L/100 km
34.1 mpg US
40.9 mpg UK
6.8 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
BMWZ4 (E89)30i
173 hp/t
129 kW/t
5.8 kg/hp
8.5 L/100 km
27.7 mpg US
33.2 mpg UK
BMWZ4 (G29)20i
139 hp/t
103 kW/t
7.2 kg/hp
6.9 L/100 km
34.1 mpg US
40.9 mpg UK

Detailed score breakdown

Detailed score breakdown
VehicleBMWZ4 (E89)30iBMWZ4 (G29)20i
Power
258 hp
192 kW
197 hp
147 kW
Torque
315 Nm
232 lb-ft
320 Nm
236 lb-ft
Acceleration
5.8 s
6.8 s
Top speed
Unrestricted
260 km/h162 mph
Restricted
250 km/h155 mph
241 km/h
150 mph
Lightness
1,490 kg
3,285 lb
1,420 kg
3,131 lb
Fuel consumption
8.5 L/100 km
27.7 mpg US
33.2 mpg UK
6.9 L/100 km
34.1 mpg US
40.9 mpg UK
Practicality
Doors/seats
2 doors
2 seats
Trunk
180 L
6.4 cu ft
Length
4,239 mm
166.9 in
Height
1,291 mm
50.8 in
Doors/seats
2 doors
2 seats
Trunk
281 L
9.9 cu ft
Length
4,324 mm
170.2 in
Height
1,304 mm
51.3 in
Range score
647 km
402 mi
754 km
468 mi
Trunk score
180 L
6.4 cu ft
281 L
9.9 cu ft
Power-to-weight score
173 hp/t
129 kW/t
5.8 kg/hp
139 hp/t
103 kW/t
7.2 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 Z4 (E89) 30iBMW Z4 (G29) 20i
Consumption8.5 L/100 km27.7 mpg US33.2 mpg UK6.9 L/100 km34.1 mpg US40.9 mpg UK
Cost / 100 km14.88 LC100 km12.08 LC100 km
Cost / 100 mi23.94 LC100 mi19.43 LC100 mi
Annual fuel used1,275 L337 US gal280 UK gal1,035 L273 US gal228 UK gal
Annual fuel cost2,231 LC/year1,811 LC/year

Head-to-head comparisons

BMW Z4 (E89) 30i

  • Has 61 hp more
  • Is 1.0 s quicker from 0-100 km/h
  • Has 19 km/h (12 mph) higher top speed
  • Has 34 hp/t better power-to-weight

Pros

  • Quickest 0-100 km/h in this comparison
  • Highest top speed
  • Most powerful
  • Best power-to-weight ratio

Cons

  • Highest combined fuel consumption
  • Heaviest
  • Smallest trunk

BMW Z4 (G29) 20i

  • Has 5 Nm more
  • Is 70 kg lighter
  • Uses 1.6 L/100 km less fuel
  • Has 107 km (66 mi) more estimated range
  • Has 101 L more trunk volume

Pros

  • Highest torque
  • Lightest
  • Lowest combined fuel consumption
  • Best estimated range
  • Largest trunk

Cons

  • Slowest 0-100 km/h
  • Lowest power
  • Lowest top speed

Choose cars to compare

Brand
Model
Generation
Engine or modification
BMW Z4 (E89) 30i
BMW Z4 (G29) 20i
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2 vehicles selected

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