165/70R14 vs 175/65R14
Switching from 165/70R14 to 175/65R14 decreases the overall diameter by 3.5 mm (0.6%). That is within the usual ±3% guideline.
| 165/70R14 | 175/65R14 | Difference (mm / revs) | |
|---|---|---|---|
| Section width | 165 mm | 175 mm | +10.0 |
| Sidewall height | 115.5 mm | 113.8 mm | -1.7 |
| Rim diameter | 355.6 mm | 355.6 mm | +0.0 |
| Overall diameter | 586.6 mm | 583.1 mm | -3.5 |
| Circumference | 1,842.9 mm | 1,831.9 mm | -11.0 |
| Revolutions | 543 per km | 546 per km | +3.0 |
Speedometer effect
With 175/65R14 fitted on a car calibrated for 165/70R14, the real speed when the speedometer shows:
| Speedometer shows | Actual speed |
|---|---|
| 50 km/h | 49.7 km/h |
| 80 km/h | 79.5 km/h |
| 100 km/h | 99.4 km/h |
| 120 km/h | 119.3 km/h |
Smaller tires make the speedometer read higher than the actual speed. 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 175 mm tire has a manufacturer-specified rim width range.
165/70R14 dimensions · 175/65R14 dimensions · Open in calculator