Tire sidewall numbers deciphered AKA wheel diameter

slant6billy

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This helpful algebra will allow you to size up those next big meaty tires. My tire guy teaches junior highschool math.... (well he is a substitute for $125 bucks a day)

Wheel diameter calculation

Width/Aspect Ratio/R (rim diameter)

(2*AR*W)/2540+rim Dia = height of tire (outside diameter)

Example: 285/40R17

(2*40*285)/2540 + 17 = 25.976” (inches)

NOTE: THIS DOES NOT ACCOUNT FOR OFFSET OR OTHER STEERING GEOMETRY/ SUSPENSION GEOMETRY.
 
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