215/70R16 vs 235/60R17

Switching from 215/70R16 to 235/60R17 increases the overall diameter by 6.4 mm (0.9%). That is within the usual ±3% guideline.

215/70R16235/60R17Difference (mm / revs)
Section width215 mm235 mm+20.0
Sidewall height150.5 mm141.0 mm-9.5
Rim diameter406.4 mm431.8 mm+25.4
Overall diameter707.4 mm713.8 mm+6.4
Circumference2,222.4 mm2,242.5 mm+20.1
Revolutions450 per km446 per km-4.0

Speedometer effect

With 235/60R17 fitted on a car calibrated for 215/70R16, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h50.5 km/h
80 km/h80.7 km/h
100 km/h100.9 km/h
120 km/h121.1 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

215/70R16 dimensions · 235/60R17 dimensions · Open in calculator