205/70R14 vs 215/70R14
Going from one to the other changes the overall height by +2.2 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 205/70R14 | 215/70R14 | Change |
|---|---|---|---|
| Overall height | 25.3" | 25.9" | +2.2 % |
| Sidewall | 5.65" | 5.93" | +4.9 % |
| Section width | 205 mm | 215 mm | +4.9 % |
| Circumference | 79.5" | 81.2" | +2.2 % |
| Revs per mile | 797 | 780 | -2.2 % |
| Axle height | 12.65" | 12.93" | +7.0 mm |
| Approved rim width | 5.5–7.5" | 6–8" | overlap 6–7.5" |
Both are approved on a rim 6" to 7.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 205/70R14. Fit 215/70R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.7 mph | +0.7 |
| 50 mph | 51.1 mph | +1.1 |
| 70 mph | 71.5 mph | +1.5 |
| 90 mph | 92.0 mph | +2.0 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,218 on the road, so it under-counts by 218. At a true 70 mph the first turns 930 times a minute, the second 910.