205/40R17 vs 215/40R17

Switching from 205/40R17 to 215/40R17 increases the overall diameter by 8.0 mm (1.3%). That is within the usual ±3% guideline.

205/40R17215/40R17Difference (mm / revs)
Section width205 mm215 mm+10.0
Sidewall height82.0 mm86.0 mm+4.0
Rim diameter431.8 mm431.8 mm+0.0
Overall diameter595.8 mm603.8 mm+8.0
Circumference1,871.8 mm1,896.9 mm+25.1
Revolutions534 per km527 per km-7.0

Speedometer effect

With 215/40R17 fitted on a car calibrated for 205/40R17, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h50.7 km/h
80 km/h81.1 km/h
100 km/h101.3 km/h
120 km/h121.6 km/h

Larger tires make the car go faster than the speedometer shows. Most speedometers also read slightly high from the factory.

Before you change size

205/40R17 dimensions · 215/40R17 dimensions · Open in calculator