165/70R14 vs 195/55R15
Switching from 165/70R14 to 195/55R15 increases the overall diameter by 8.9 mm (1.5%). That is within the usual ±3% guideline.
| 165/70R14 | 195/55R15 | Difference (mm / revs) | |
|---|---|---|---|
| Section width | 165 mm | 195 mm | +30.0 |
| Sidewall height | 115.5 mm | 107.2 mm | -8.3 |
| Rim diameter | 355.6 mm | 381.0 mm | +25.4 |
| Overall diameter | 586.6 mm | 595.5 mm | +8.9 |
| Circumference | 1,842.9 mm | 1,870.8 mm | +27.9 |
| Revolutions | 543 per km | 535 per km | -8.0 |
Speedometer effect
With 195/55R15 fitted on a car calibrated for 165/70R14, the real speed when the speedometer shows:
| Speedometer shows | Actual speed |
|---|---|
| 50 km/h | 50.8 km/h |
| 80 km/h | 81.2 km/h |
| 100 km/h | 101.5 km/h |
| 120 km/h | 121.8 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 195 mm tire has a manufacturer-specified rim width range.
165/70R14 dimensions · 195/55R15 dimensions · Open in calculator