Speedometer Error Calculator
Estimate speedometer error after tire size changes.
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What This Calculator Does
Estimate speedometer error after tire size changes.
It combines Original Tire Diameter, New Tire Diameter, Indicated Speed to estimate Actual Speed, Speedometer Error.
Formula & Method
Core equations: Diameter ratio method: \text{Actual Speed} = \text{Indicated}\cdot \frac{D_{new}}{D_{stock}} and error% =\left(\frac{D_{new}}{D_{stock}}-1\right)\cdot100.
Notation used in the formulas: R = Actual Speed; x_{1} = Original Tire Diameter; x_{2} = New Tire Diameter; x_{3} = Indicated Speed.
Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.
Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.
Inputs Used
- Original Tire Diameter: Used directly in the calculation.
- New Tire Diameter: Used directly in the calculation.
- Indicated Speed: Used directly in the calculation.
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