215/65R17 vs 235/65R16

Switching from 215/65R17 to 235/65R16 increases the overall diameter by 0.6 mm (0.1%). That is within the usual ±3% guideline.

215/65R17235/65R16Difference (mm / revs)
Section width215 mm235 mm+20.0
Sidewall height139.8 mm152.8 mm+13.0
Rim diameter431.8 mm406.4 mm-25.4
Overall diameter711.3 mm711.9 mm+0.6
Circumference2,234.6 mm2,236.5 mm+1.9
Revolutions448 per km447 per km-1.0

Speedometer effect

With 235/65R16 fitted on a car calibrated for 215/65R17, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h50.0 km/h
80 km/h80.1 km/h
100 km/h100.1 km/h
120 km/h120.1 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

215/65R17 dimensions · 235/65R16 dimensions · Open in calculator