Car comparison

Porsche Boxster (987) · Facelift 2009 S 3.4vsMercedes-Benz SLK (R171) · Facelift 2008 SLK 350 V6

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

New comparison

Porsche Boxster (987) · Facelift 2009

S 3.4

310 hp3436 ccGasolineRWDAutomaticNaturally aspiratedRoadster2009-2012
VS

Mercedes-Benz SLK (R171) · Facelift 2008

SLK 350 V6

305 hp3498 ccGasolineRWDAutomaticNaturally aspiratedRoadster2008-2011

Comparison overview

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

Best choices

Porsche Boxster (987) Facelift 2009 S 3.4

  • Quickest 0-100 km/h
    5.2 s
  • Fastest top speed
    272 km/h
    169 mph
  • Most powerful
    310 hp
    231 kW
  • Highest torque
    360 Nm
    266 lb-ft
  • Lightest
    1,380 kg
    3,042 lb
  • Best power-to-weight
    225 hp/t
    168 kW/t
    4.5 kg/hp
  • Lowest highway consumption
    6.6 L/100 km
    35.6 mpg US
    42.8 mpg UK
  • Best overall score
    55/100
  • Best performance score
    68/100

Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6

  • Lowest combined fuel consumption
    9.0 L/100 km
    26.1 mpg US
    31.4 mpg UK
  • Lowest city consumption
    12.6 L/100 km
    18.7 mpg US
    22.4 mpg UK
  • Best estimated range
    778 km
    483 mi
  • Largest trunk
    208 L
  • Best economy score
    83/100
  • Best practicality score
    29/100

Specification comparison

Specification comparison
ModelPorscheBoxster (987)Facelift 2009S 3.4Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
Power
310hp231kW
305hp227kW
Torque
360Nm266lb-ft
360Nm266lb-ft
Curb weight
1,380kg3,042lb
1,430kg3,153lb
Gross weight
1,675kg3,693lb
1,800kg3,968lb
Top speed
272 km/h
169 mph
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Calculated
To 99% top speed
78.5s99% target: 269 km/h / 167 mph
Calculated
68.7s99% target: 262 km/h / 163 mph
Calculated
0-100 km/h
5.2s
5.4s
0-200 km/h
18.2s
18.2s
Calculated
0-60 mph
4.9s
Calculated
5.1s
Calculated
Fuel consumption
9.4L/100 km25mpg US30.1mpg UK
9L/100 km26.1mpg US31.4mpg UK
Fuel consumption city
14.1L/100 km16.7mpg US20.0mpg UK
12.6L/100 km18.7mpg US22.4mpg UK
Fuel consumption highway
6.6L/100 km35.6mpg US42.8mpg UK
6.9L/100 km34.1mpg US40.9mpg UK
Quarter mile
13.3s
Calculated
13.5s
Calculated
Power-to-weight
225hp/t168kW/t102hp/1000 lb
Calculated
213hp/t159kW/t97hp/1000 lb
Calculated
Torque-to-weight
261Nm/t175lb-ft/ton
Calculated
252Nm/t168lb-ft/ton
Calculated
Estimated range
691km430mi
Calculated
778km483mi
Calculated
Displacement
3,436cc210cu in
3,498cc213cu in
Length
4,342mm171in
4,107mm162in
Width
1,801mm71in
1,788mm70in
Height
1,294mm51in
1,298mm51in
Wheelbase
2,415mm95in
2,430mm96in
Front track
1,486mm59in
1,525mm60in
Rear track
1,528mm60in
1,550mm61in
Ground clearance
123mm5in
-
Trunk volume
130L
208L
Doors
2
2
Seats
2
2
Fuel tank
65L
70L
CO2 emissions
221g/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 (987) Facelift 2009 S 3.4Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6PowerTorque
  • Porsche Boxster (987) Facelift 2009 S 3.4: Power / Torque
  • Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6: Power / Torque
Dyno simulation data table
VehiclePeak power RPMPeak torque RPMMax engine speed
PorscheBoxster (987)Facelift 2009S 3.47,200 rpm4,750 rpm7,500 rpm
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V66,500 rpm4,900 rpm6,750 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
MetricPorscheBoxster (987)Facelift 2009S 3.4Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
Acceleration checkpoints
0-60 mph
0-97 km/h
4.9 s
5.1 s
0-100 km/h
0-62 mph
5.2 s
5.4 s
0-200 km/h
0-124 mph
18.2 s
18.2 s
Top speed
272 km/h
169 mph
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Limited
Drag race simulation
60 ft
18 m
2.2 s
2.3 s
330 ft
101 m
5.8 s
5.9 s
1/8 mile
201 m
8.7 s
8.9 s
1000 ft
305 m
11.2 s
11.4 s
1/4 mile
402 m
13.3 s
13.5 s
Trap speed
1/4 mile
402 m
174 km/h
108 mph
174 km/h
108 mph

Power comparison

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

Chart data table
VehicleValue
PorscheBoxster (987)Facelift 2009S 3.4
310 hp
231 kW
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
305 hp
227 kW

Porsche Boxster (987) Facelift 2009 S 3.4 has 5 hp more than Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6.

The biggest power difference is between Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6 and Porsche Boxster (987) Facelift 2009 S 3.4: 5 hp (4 kW).

Torque comparison

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

Chart data table
VehicleValue
PorscheBoxster (987)Facelift 2009S 3.4
360 Nm
266 lb-ft
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
360 Nm
266 lb-ft

Curb weight comparison

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

Chart data table
VehicleValue
PorscheBoxster (987)Facelift 2009S 3.4
1,380 kg
3,042 lb
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
1,430 kg
3,153 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 (987)Facelift 2009S 3.4
272 km/h
169 mph
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
Unrestricted
265 km/h165 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 (987)Facelift 2009S 3.45.2 s
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V65.4 s

The biggest 0-100 km/h difference is between Porsche Boxster (987) Facelift 2009 S 3.4 and Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6: 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
PorscheBoxster (987)Facelift 2009S 3.4
9.4 L/100 km
25.0 mpg US
30.1 mpg UK
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
9.0 L/100 km
26.1 mpg US
31.4 mpg UK

Power-to-weight comparison

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

Chart data table
VehicleValue
PorscheBoxster (987)Facelift 2009S 3.4
225 hp/t
168 kW/t
4.5 kg/hp
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
213 hp/t
159 kW/t
4.7 kg/hp

Estimated range comparison

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

Chart data table
VehicleValue
PorscheBoxster (987)Facelift 2009S 3.4
691 km
430 mi
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
778 km
483 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
VehiclePowerAccelerationTop speed
PorscheBoxster (987)Facelift 2009S 3.4
310 hp
231 kW
5.2 s
272 km/h
169 mph
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
305 hp
227 kW
5.4 s
Unrestricted
265 km/h165 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 (987)Facelift 2009S 3.4
Power
310 hp
231 kW
0-100 km/h5.2 s
Top speed
272 km/h
169 mph
Doors/seats
2 doors
2 seats
Trunk
130 L
4.6 cu ft
Length
4,342 mm
170.9 in
Height
1,294 mm
50.9 in
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
Power
305 hp
227 kW
0-100 km/h5.4 s
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Doors/seats
2 doors
2 seats
Trunk
208 L
7.3 cu ft
Length
4,107 mm
161.7 in
Height
1,298 mm
51.1 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 (987)Facelift 2009S 3.4
Power
310 hp
231 kW
0-100 km/h5.2 s
Top speed
272 km/h
169 mph
9.4 L/100 km
25.0 mpg US
30.1 mpg UK
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
Power
305 hp
227 kW
0-100 km/h5.4 s
Top speed
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
9.0 L/100 km
26.1 mpg US
31.4 mpg UK

Porsche Boxster (987) Facelift 2009 S 3.4 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 (987)Facelift 2009S 3.4
9.4 L/100 km
25.0 mpg US
30.1 mpg UK
5.2 s
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
9.0 L/100 km
26.1 mpg US
31.4 mpg UK
5.4 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 (987)Facelift 2009S 3.4
225 hp/t
168 kW/t
4.5 kg/hp
9.4 L/100 km
25.0 mpg US
30.1 mpg UK
Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
213 hp/t
159 kW/t
4.7 kg/hp
9.0 L/100 km
26.1 mpg US
31.4 mpg UK

Detailed score breakdown

Detailed score breakdown
VehiclePorscheBoxster (987)Facelift 2009S 3.4Mercedes-BenzSLK (R171)Facelift 2008SLK 350 V6
Power
310 hp
231 kW
305 hp
227 kW
Torque
360 Nm
266 lb-ft
360 Nm
266 lb-ft
Acceleration
5.2 s
5.4 s
Top speed
272 km/h
169 mph
Unrestricted
265 km/h165 mph
Restricted
250 km/h155 mph
Lightness
1,380 kg
3,042 lb
1,430 kg
3,153 lb
Fuel consumption
9.4 L/100 km
25.0 mpg US
30.1 mpg UK
9.0 L/100 km
26.1 mpg US
31.4 mpg UK
Practicality
Doors/seats
2 doors
2 seats
Trunk
130 L
4.6 cu ft
Length
4,342 mm
170.9 in
Height
1,294 mm
50.9 in
Doors/seats
2 doors
2 seats
Trunk
208 L
7.3 cu ft
Length
4,107 mm
161.7 in
Height
1,298 mm
51.1 in
Range score
691 km
430 mi
778 km
483 mi
CO2 score
221 g/km
-
Trunk score
130 L
4.6 cu ft
208 L
7.3 cu ft
Power-to-weight score
225 hp/t
168 kW/t
4.5 kg/hp
213 hp/t
159 kW/t
4.7 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 (987) Facelift 2009 S 3.4Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6
Consumption9.4 L/100 km25 mpg US30.1 mpg UK9 L/100 km26.1 mpg US31.4 mpg UK
Cost / 100 km16.45 LC100 km15.75 LC100 km
Cost / 100 mi26.47 LC100 mi25.35 LC100 mi
Annual fuel used1,410 L372 US gal310 UK gal1,350 L357 US gal297 UK gal
Annual fuel cost2,468 LC/year2,363 LC/year

Head-to-head comparisons

Porsche Boxster (987) Facelift 2009 S 3.4

  • Has 5 hp more
  • Is 50 kg lighter
  • Is 0.2 s quicker from 0-100 km/h
  • Has 7 km/h (4 mph) higher top speed
  • Has 11 hp/t better power-to-weight

Pros

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

Cons

  • Highest combined fuel consumption
  • Smallest trunk

Mercedes-Benz SLK (R171) Facelift 2008 SLK 350 V6

  • Uses 0.4 L/100 km less fuel
  • Has 86 km (54 mi) more estimated range
  • Has 78 L more trunk volume

Pros

  • Lowest combined fuel consumption
  • Best estimated range
  • Largest trunk

Cons

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

Choose cars to compare

Brand
Model
Generation
Engine or modification
Porsche Boxster (987) S 3.4
Mercedes-Benz SLK (R171) SLK 350 V6
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2 vehicles selected

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