175/65R15 vs 205/50R16
Switching from 175/65R15 to 205/50R16 increases the overall diameter by 2.9 mm (0.5%). That is within the usual ±3% guideline.
| 175/65R15 | 205/50R16 | Difference (mm / revs) | |
|---|---|---|---|
| Section width | 175 mm | 205 mm | +30.0 |
| Sidewall height | 113.8 mm | 102.5 mm | -11.3 |
| Rim diameter | 381.0 mm | 406.4 mm | +25.4 |
| Overall diameter | 608.5 mm | 611.4 mm | +2.9 |
| Circumference | 1,911.7 mm | 1,920.8 mm | +9.1 |
| Revolutions | 523 per km | 521 per km | -2.0 |
Speedometer effect
With 205/50R16 fitted on a car calibrated for 175/65R15, the real speed when the speedometer shows:
| Speedometer shows | Actual speed |
|---|---|
| 50 km/h | 50.2 km/h |
| 80 km/h | 80.4 km/h |
| 100 km/h | 100.5 km/h |
| 120 km/h | 120.6 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
- Check the sizes approved for your vehicle on the door-jamb placard or in the owner's manual.
- Check clearance to suspension, brakes and arches at full lock and full compression.
- Match or exceed the original load index and speed rating.
- Wider tires need an appropriate rim width; a 205 mm tire has a manufacturer-specified rim width range.
175/65R15 dimensions · 205/50R16 dimensions · Open in calculator