155/80R13 vs 165/70R14
Switching from 155/80R13 to 165/70R14 increases the overall diameter by 8.4 mm (1.5%). That is within the usual ±3% guideline.
| 155/80R13 | 165/70R14 | Difference (mm / revs) | |
|---|---|---|---|
| Section width | 155 mm | 165 mm | +10.0 |
| Sidewall height | 124.0 mm | 115.5 mm | -8.5 |
| Rim diameter | 330.2 mm | 355.6 mm | +25.4 |
| Overall diameter | 578.2 mm | 586.6 mm | +8.4 |
| Circumference | 1,816.5 mm | 1,842.9 mm | +26.4 |
| Revolutions | 551 per km | 543 per km | -8.0 |
Speedometer effect
With 165/70R14 fitted on a car calibrated for 155/80R13, the real speed when the speedometer shows:
| Speedometer shows | Actual speed |
|---|---|
| 50 km/h | 50.7 km/h |
| 80 km/h | 81.2 km/h |
| 100 km/h | 101.5 km/h |
| 120 km/h | 121.7 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 165 mm tire has a manufacturer-specified rim width range.
155/80R13 dimensions · 165/70R14 dimensions · Open in calculator