Power Hungry Performance Forum FAQ

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Tire Size and Rev per Mile Calculator

Use this calculator to determine the tire diameter and revolutions per mile for a given tire size.

This calculator is for informational purposes only and does not take into account variables such as variations in tread depth or inflation pressure.

Please consult your tire manufacturer's documentation for additional information and specifications.
Tire Tread Width
Sidewall Aspect Ratio
Wheel Diameter
Tire Squish%
Tire Diameter (in inches)
Tire Diameter (in mm)
Tire Circumference (in inches)
Tire Circumference (in mm)
Revolutions per Mile

Miscellaneous Calculators

Miscellaneous Calculators
 

Calculate HP from 1/4 Mile Trap Speed

Vehicle weight in pounds (including driver)
 lbs
1/4 mile Trap Speed in M.P.H.
 M.P.H.


You are making:  HP at the rear wheels and  HP at the flywheel*.

JavaScript must be enabled in your browser for the calculation to work.

*Note:  Assuming a 20% drive train loss.


Calculate HP from 1/4 Mile ET

Vehicle weight in pounds (including driver)
 Lbs
1/4 Mile ET in seconds
 Sec


You are making:  HP at the rear wheels and  HP at the flywheel*.

JavaScript must be enabled in your browser for the calculation to work.

*Note:  Assuming a 20% drive train loss.


Calculate Tire Diameter

Tire width - Series - Wheel Diameter
Example 275 - 60 R 15
Tire Width
Tire Series
Wheel Diameter



The tire diameter is  inches and  Revs per Mile

JavaScript must be enabled in your browser for the calculation to work.

*Note:  Does not account for tread loss or inflation pressure.


Calculate MPH for RPM range

  Tire Diam. Inch
Trans Ratio
Axle Ratio
 

  1000 RPM   MPH 4500 RPM   MPH  
  1250 RPM   MPH 4750 RPM   MPH  
  1500 RPM   MPH 5000 RPM   MPH  
  1750 RPM   MPH 5250 RPM   MPH  
  2000 RPM   MPH 5500 RPM   MPH  
  2250 RPM   MPH 5750 RPM   MPH  
  2500 RPM   MPH 6000 RPM   MPH  
  2750 RPM   MPH 6250 RPM   MPH  
  3000 RPM   MPH 6500 RPM   MPH  
  3250 RPM   MPH 6750 RPM   MPH  
  3500 RPM   MPH 7000 RPM   MPH  
  3750 RPM   MPH 7250 RPM   MPH  
  4000 RPM   MPH 7500 RPM   MPH  
  4250 RPM   MPH 7750 RPM   MPH  

JavaScript must be enabled in your browser for the calculation to work.



Calculate Rear End Gear Ratio

Enter the tire diameter in inches, rpm's of the motor at a certain speed as indicated by your speedometer in MPH. This calculation assumes the car's transmission is in drive or 1:1 ratio, no overdrive.
Tire Diameter (in)
RPM
Speed at RPM (MPH)


Rear End Gear Ratio

JavaScript must be enabled in your browser for the calculation to work.

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