215/45R19 vs 205/50R19
Going from one to the other changes the overall height by +1.7 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 215/45R19 | 205/50R19 | Change |
|---|---|---|---|
| Overall height | 26.6" | 27.1" | +1.7 % |
| Sidewall | 3.81" | 4.04" | +5.9 % |
| Section width | 215 mm | 205 mm | -4.7 % |
| Circumference | 83.6" | 85.0" | +1.7 % |
| Revs per mile | 758 | 745 | -1.7 % |
| Axle height | 13.31" | 13.54" | +5.8 mm |
| Approved rim width | 6–8" | 5.5–7.5" | 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 215/45R19. Fit 205/50R19 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.5 mph | +0.5 |
| 50 mph | 50.9 mph | +0.9 |
| 70 mph | 71.2 mph | +1.2 |
| 90 mph | 91.5 mph | +1.5 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,170 on the road, so it under-counts by 170. At a true 70 mph the first turns 884 times a minute, the second 869.