Car comparison

Porsche Boxster (981) Spyder 3.8vsMercedes-Benz SLK (R172) AMG SLK 55 V8

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

New comparison

Porsche Boxster (981)

Spyder 3.8

375 hp3800 ccGasolineRWDManualNaturally aspiratedRoadster2015-2016
VS

Mercedes-Benz SLK (R172)

AMG SLK 55 V8

421 hp5461 ccGasolineRWDAutomaticNaturally aspiratedRoadster2012-2015

Comparison overview

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

Best choices

Mercedes-Benz SLK (R172) AMG SLK 55 V8

  • Most powerful
    421 hp
    314 kW
  • Highest torque
    540 Nm
    398 lb-ft
  • Lowest combined fuel consumption
    8.4 L/100 km
    28.0 mpg US
    33.6 mpg UK
  • Lowest city consumption
    12.0 L/100 km
    19.6 mpg US
    23.5 mpg UK
  • Lowest highway consumption
    6.2 L/100 km
    37.9 mpg US
    45.6 mpg UK
  • Best estimated range
    833 km
    518 mi
  • Best performance score
    78/100
  • Best economy score
    84/100

Porsche Boxster (981) Spyder 3.8

  • Quickest 0-100 km/h
    4.5 s
  • Fastest top speed
    300 km/h
    186 mph Unrestricted
    290 km/h
    180 mph Restricted
  • Lightest
    1,315 kg
    2,899 lb
  • Best power-to-weight
    285 hp/t
    213 kW/t
    3.5 kg/hp
  • Largest trunk
    280 L
  • Best overall score
    62/100
  • Best practicality score
    31/100

Specification comparison

Specification comparison
ModelPorscheBoxster (981)Spyder 3.8Mercedes-BenzSLK (R172)AMG SLK 55 V8
Power
375hp280kW
421hp314kW
Torque
420Nm310lb-ft
540Nm398lb-ft
Curb weight
1,315kg2,899lb
1,535kg3,384lb
Gross weight
1,650kg3,638lb
1,910kg4,211lb
Top speed
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
Calculated
Unrestricted
270 km/h168 mph
Restricted
250 km/h155 mph
Calculated
To 99% top speed
61.8s99% target: 297 km/h / 185 mph
Calculated
58.1s99% target: 267 km/h / 166 mph
Calculated
0-100 km/h
4.5s
4.6s
0-200 km/h
13.2s
Calculated
15.0s
Calculated
0-60 mph
4.3s
Calculated
4.4s
Calculated
Fuel consumption
9.9L/100 km23.8mpg US28.5mpg UK
8.4L/100 km28mpg US33.6mpg UK
Fuel consumption city
14.2L/100 km16.6mpg US19.9mpg UK
12L/100 km19.6mpg US23.5mpg UK
Fuel consumption highway
7.5L/100 km31.4mpg US37.7mpg UK
6.2L/100 km37.9mpg US45.6mpg UK
Quarter mile
12.4s
Calculated
12.6s
Calculated
Power-to-weight
285hp/t213kW/t129hp/1000 lb
Calculated
274hp/t205kW/t124hp/1000 lb
Calculated
Torque-to-weight
319Nm/t214lb-ft/ton
Calculated
352Nm/t235lb-ft/ton
Calculated
Estimated range
545km339mi
Calculated
833km518mi
Calculated
Displacement
3,800cc232cu in
5,461cc333cu in
Length
4,414mm174in
4,134mm163in
Width
1,801mm71in
1,810mm71in
Height
1,262mm50in
1,301mm51in
Wheelbase
2,475mm97in
2,430mm96in
Front track
1,526mm60in
1,559mm61in
Rear track
1,540mm61in
1,565mm62in
Ground clearance
106mm4in
-
Trunk volume
280L
225L
Max trunk volume-
335L
Doors
2
2
Seats
2
2
Fuel tank
54L
70L
CO2 emissions-
195g/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.

Porsche Boxster (981) Spyder 3.8Mercedes-Benz SLK (R172) AMG SLK 55 V8PowerTorque
  • Porsche Boxster (981) Spyder 3.8: Power / Torque
  • Mercedes-Benz SLK (R172) AMG SLK 55 V8: Power / Torque
Dyno simulation data table
VehiclePeak power RPMPeak torque RPMMax engine speed
PorscheBoxster (981)Spyder 3.86,700 rpm4,750-6,000 rpm6,950 rpm
Mercedes-BenzSLK (R172)AMG SLK 55 V86,800 rpm4,500 rpm7,050 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
MetricPorscheBoxster (981)Spyder 3.8Mercedes-BenzSLK (R172)AMG SLK 55 V8
Acceleration checkpoints
0-60 mph
0-97 km/h
4.3 s
4.4 s
0-100 km/h
0-62 mph
4.5 s
4.6 s
0-200 km/h
0-124 mph
13.2 s
15.0 s
Top speed
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
Likely limited
Unrestricted
270 km/h168 mph
Restricted
250 km/h155 mph
Limited
Drag race simulation
60 ft
18 m
2.2 s
2.2 s
330 ft
101 m
5.5 s
5.6 s
1/8 mile
201 m
8.2 s
8.3 s
1000 ft
305 m
10.5 s
10.7 s
1/4 mile
402 m
12.4 s
12.6 s
Trap speed
1/4 mile
402 m
194 km/h
120 mph
185 km/h
115 mph

Power comparison

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

Chart data table
VehicleValue
PorscheBoxster (981)Spyder 3.8
375 hp
280 kW
Mercedes-BenzSLK (R172)AMG SLK 55 V8
421 hp
314 kW

Mercedes-Benz SLK (R172) AMG SLK 55 V8 has 46 hp more than Porsche Boxster (981) Spyder 3.8.

The biggest power difference is between Porsche Boxster (981) Spyder 3.8 and Mercedes-Benz SLK (R172) AMG SLK 55 V8: 46 hp (34 kW).

Torque comparison

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

Chart data table
VehicleValue
PorscheBoxster (981)Spyder 3.8
420 Nm
310 lb-ft
Mercedes-BenzSLK (R172)AMG SLK 55 V8
540 Nm
398 lb-ft

Curb weight comparison

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

Chart data table
VehicleValue
PorscheBoxster (981)Spyder 3.8
1,315 kg
2,899 lb
Mercedes-BenzSLK (R172)AMG SLK 55 V8
1,535 kg
3,384 lb

Top speed without limiter comparison

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

Chart data table
VehicleValue
PorscheBoxster (981)Spyder 3.8
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
Mercedes-BenzSLK (R172)AMG SLK 55 V8
Unrestricted
270 km/h168 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
PorscheBoxster (981)Spyder 3.84.5 s
Mercedes-BenzSLK (R172)AMG SLK 55 V84.6 s

Although Mercedes-Benz SLK (R172) AMG SLK 55 V8 has more power, Porsche Boxster (981) Spyder 3.8 is quicker from 0-100 km/h.

The biggest 0-100 km/h difference is between Porsche Boxster (981) Spyder 3.8 and Mercedes-Benz SLK (R172) AMG SLK 55 V8: 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
VehicleValue
PorscheBoxster (981)Spyder 3.8
9.9 L/100 km
23.8 mpg US
28.5 mpg UK
Mercedes-BenzSLK (R172)AMG SLK 55 V8
8.4 L/100 km
28.0 mpg US
33.6 mpg UK

The biggest fuel consumption difference is between Mercedes-Benz SLK (R172) AMG SLK 55 V8 and Porsche Boxster (981) Spyder 3.8: 1.5 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
PorscheBoxster (981)Spyder 3.8
285 hp/t
213 kW/t
3.5 kg/hp
Mercedes-BenzSLK (R172)AMG SLK 55 V8
274 hp/t
205 kW/t
3.6 kg/hp

Estimated range comparison

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

Chart data table
VehicleValue
PorscheBoxster (981)Spyder 3.8
545 km
339 mi
Mercedes-BenzSLK (R172)AMG SLK 55 V8
833 km
518 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
VehiclePowerAccelerationTop speed
PorscheBoxster (981)Spyder 3.8
375 hp
280 kW
4.5 s
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
Mercedes-BenzSLK (R172)AMG SLK 55 V8
421 hp
314 kW
4.6 s
Unrestricted
270 km/h168 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
PorscheBoxster (981)Spyder 3.8
Power
375 hp
280 kW
0-100 km/h4.5 s
Top speed
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
Doors/seats
2 doors
2 seats
Trunk
280 L
9.9 cu ft
Length
4,414 mm
173.8 in
Height
1,262 mm
49.7 in
Mercedes-BenzSLK (R172)AMG SLK 55 V8
Power
421 hp
314 kW
0-100 km/h4.6 s
Top speed
Unrestricted
270 km/h168 mph
Restricted
250 km/h155 mph
Doors/seats
2 doors
2 seats
Trunk
225 L
7.9 cu ft
Length
4,134 mm
162.8 in
Height
1,301 mm
51.2 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
PorscheBoxster (981)Spyder 3.8
Power
375 hp
280 kW
0-100 km/h4.5 s
Top speed
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
9.9 L/100 km
23.8 mpg US
28.5 mpg UK
Mercedes-BenzSLK (R172)AMG SLK 55 V8
Power
421 hp
314 kW
0-100 km/h4.6 s
Top speed
Unrestricted
270 km/h168 mph
Restricted
250 km/h155 mph
8.4 L/100 km
28.0 mpg US
33.6 mpg UK

Mercedes-Benz SLK (R172) AMG SLK 55 V8 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
PorscheBoxster (981)Spyder 3.8
9.9 L/100 km
23.8 mpg US
28.5 mpg UK
4.5 s
Mercedes-BenzSLK (R172)AMG SLK 55 V8
8.4 L/100 km
28.0 mpg US
33.6 mpg UK
4.6 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
VehiclePower-to-weight, hp/tFuel consumption, L/100 km
PorscheBoxster (981)Spyder 3.8
285 hp/t
213 kW/t
3.5 kg/hp
9.9 L/100 km
23.8 mpg US
28.5 mpg UK
Mercedes-BenzSLK (R172)AMG SLK 55 V8
274 hp/t
205 kW/t
3.6 kg/hp
8.4 L/100 km
28.0 mpg US
33.6 mpg UK

Detailed score breakdown

Detailed score breakdown
VehiclePorscheBoxster (981)Spyder 3.8Mercedes-BenzSLK (R172)AMG SLK 55 V8
Power
375 hp
280 kW
421 hp
314 kW
Torque
420 Nm
310 lb-ft
540 Nm
398 lb-ft
Acceleration
4.5 s
4.6 s
Top speed
Unrestricted
300 km/h186 mph
Restricted
290 km/h180 mph
Unrestricted
270 km/h168 mph
Restricted
250 km/h155 mph
Lightness
1,315 kg
2,899 lb
1,535 kg
3,384 lb
Fuel consumption
9.9 L/100 km
23.8 mpg US
28.5 mpg UK
8.4 L/100 km
28.0 mpg US
33.6 mpg UK
Practicality
Doors/seats
2 doors
2 seats
Trunk
280 L
9.9 cu ft
Length
4,414 mm
173.8 in
Height
1,262 mm
49.7 in
Doors/seats
2 doors
2 seats
Trunk
225 L
7.9 cu ft
Length
4,134 mm
162.8 in
Height
1,301 mm
51.2 in
Range score
545 km
339 mi
833 km
518 mi
CO2 score
-
195 g/km
Trunk score
280 L
9.9 cu ft
225 L
7.9 cu ft
Power-to-weight score
285 hp/t
213 kW/t
3.5 kg/hp
274 hp/t
205 kW/t
3.6 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
VehiclePorsche Boxster (981) Spyder 3.8Mercedes-Benz SLK (R172) AMG SLK 55 V8
Consumption9.9 L/100 km23.8 mpg US28.5 mpg UK8.4 L/100 km28 mpg US33.6 mpg UK
Cost / 100 km17.33 LC100 km14.70 LC100 km
Cost / 100 mi27.88 LC100 mi23.66 LC100 mi
Annual fuel used1,485 L392 US gal327 UK gal1,260 L333 US gal277 UK gal
Annual fuel cost2,599 LC/year2,205 LC/year

Head-to-head comparisons

Porsche Boxster (981) Spyder 3.8

  • Is 220 kg lighter
  • Is 0.1 s quicker from 0-100 km/h
  • Has 30 km/h (19 mph) higher top speed
  • Has 11 hp/t better power-to-weight
  • Has 55 L more trunk volume

Pros

  • Quickest 0-100 km/h in this comparison
  • Highest top speed
  • Lightest
  • Best power-to-weight ratio
  • Largest trunk

Cons

  • Lowest power
  • Highest combined fuel consumption

Mercedes-Benz SLK (R172) AMG SLK 55 V8

  • Has 46 hp more
  • Has 120 Nm more
  • Uses 1.5 L/100 km less fuel
  • Has 288 km (179 mi) more estimated range

Pros

  • Most powerful
  • Highest torque
  • Lowest combined fuel consumption
  • Best estimated range

Cons

  • Slowest 0-100 km/h
  • Heaviest
  • Lowest top speed
  • Smallest trunk

Choose cars to compare

Brand
Model
Generation
Engine or modification
Porsche Boxster (981) Spyder 3.8
Mercedes-Benz SLK (R172) AMG SLK 55 V8
Compare selected cars
2 vehicles selected

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