205/50R14 vs 215/45R14
Going from one to the other changes the overall height by -2.1 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 205/50R14 | 215/45R14 | Change |
|---|---|---|---|
| Overall height | 22.1" | 21.6" | -2.1 % |
| Sidewall | 4.04" | 3.81" | -5.6 % |
| Section width | 205 mm | 215 mm | +4.9 % |
| Circumference | 69.3" | 67.9" | -2.1 % |
| Revs per mile | 914 | 933 | +2.1 % |
| Axle height | 11.04" | 10.81" | -5.8 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 205/50R14. Fit 215/45R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.4 mph | -0.6 |
| 50 mph | 49.0 mph | -1.0 |
| 70 mph | 68.6 mph | -1.4 |
| 90 mph | 88.2 mph | -1.8 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,795 on the road, so it over-counts by 205. At a true 70 mph the first turns 1066 times a minute, the second 1088.