205/50R16 vs 195/55R16
Going from one to the other changes the overall height by +1.6 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 205/50R16 | 195/55R16 | Change |
|---|---|---|---|
| Overall height | 24.1" | 24.4" | +1.6 % |
| Sidewall | 4.04" | 4.22" | +4.6 % |
| Section width | 205 mm | 195 mm | -4.9 % |
| Circumference | 75.6" | 76.8" | +1.6 % |
| Revs per mile | 838 | 825 | -1.6 % |
| Axle height | 12.04" | 12.22" | +4.8 mm |
| Approved rim width | 5.5–7.5" | 5.5–7" | overlap 5.5–7" |
Both are approved on a rim 5.5" to 7" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 205/50R16. Fit 195/55R16 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.5 mph | +0.5 |
| 50 mph | 50.8 mph | +0.8 |
| 70 mph | 71.1 mph | +1.1 |
| 90 mph | 91.4 mph | +1.4 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,155 on the road, so it under-counts by 155. At a true 70 mph the first turns 978 times a minute, the second 963.