speedometer and rpm meter
talon_dsm
04-29-2003, 08:23 PM
does changing your rim and tire size mess up the speedometer and rpm meter? if so how much?
Cy@tirerack
05-01-2003, 03:09 PM
It depends on the tire size that you change to. When we set up a wheel and tire package we select a tire that has a shorter sidewall so that the overall diameter of tire/wheel combination does not signficantly change - we recommend staying within a 3% margin.
If the new tire diameter is 1% smaller than your speedometer will overestimate your speed by 1%. If the new tire is 1% bigger than your speedometer will underestimate your speed by 1%.
There will be no effect on your rpm meter/tachometer since it's measuring engine speed.
The bottom line is that if you stay within a 3% margin, you won't have any negative on the ABS, traction control and other systems.
If the new tire diameter is 1% smaller than your speedometer will overestimate your speed by 1%. If the new tire is 1% bigger than your speedometer will underestimate your speed by 1%.
There will be no effect on your rpm meter/tachometer since it's measuring engine speed.
The bottom line is that if you stay within a 3% margin, you won't have any negative on the ABS, traction control and other systems.
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