215/60R15 vs 195/65R15
Going from one to the other changes the overall height by -0.7 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 215/60R15 | 195/65R15 | Change |
|---|---|---|---|
| Overall height | 25.2" | 25.0" | -0.7 % |
| Sidewall | 5.08" | 4.99" | -1.7 % |
| Section width | 215 mm | 195 mm | -9.3 % |
| Circumference | 79.0" | 78.5" | -0.7 % |
| Revs per mile | 802 | 807 | +0.7 % |
| Axle height | 12.58" | 12.49" | -2.3 mm |
| Approved rim width | 6–8" | 5.5–7" | overlap 6–7" |
Both are approved on a rim 6" to 7" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 215/60R15. Fit 195/65R15 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.8 mph | -0.2 |
| 50 mph | 49.6 mph | -0.4 |
| 70 mph | 69.5 mph | -0.5 |
| 90 mph | 89.4 mph | -0.6 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,930 on the road, so it over-counts by 70. At a true 70 mph the first turns 935 times a minute, the second 942.