• 1/4 Mile HP
• 1/4 ET & MPH based on weight and HP
• 1/4 ET & MPH
• 1/4 ET & 1/8 ET
• 1/4 Mile MPH based on tire, converter slip, gear & RPM
• 1/4 Mile RPM based on tire, converter slip, MPH & rear gear
• % Converter Slip based on 1/4 Mile MPH, tire & gear
• Optimum tire height based on MPH, RPM, converter slip & rear gear
• Tire Height based on sidewall designation
• Tire Width (mm) and Aspect Ratio based on height and width (in.)
• Optimum rear gear based on tire, converter slip, MPH & RPM
• Effective & Equivalent Gear Ratios based on New and Old tire heights and original gear
• Engine Displacement
• Carburetor Sizing for Normally Aspirated Engines

¼ Mile Horsepower Calculator
MPH	Weight				HP
Enter the MPH and Weight and Click on Calculate...
HP = Weight * (MPH / 234) ^3

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¼ Mile ET & MPH Calculator #1
Weight	HP			ET	MPH
Enter the Weight and HP and Click on Calculate twice...
MPH = 234 * (HP / Weight) ^ .3333 ET = 1353 / MPH

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¼ Mile ET & MPH Calculator #2
ET			MPH
Enter the ET or MPH and Click on Calculate...
ET = 1353 / MPH MPH = 1353 / ET

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¼ Mile ET & 1/8 Mile ET Conversions
¼ Mile ET			1/8 Mile ET
Enter the ¼ Mile ET or the 1/8 Mile ET and Click on Calculate...
¼ Mile ET = (1/8 Mile ET + .22) / .655 1/8 Mile ET = (¼ Mile ET * .655) - .22

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% Converter Slip Calculator
RPM	Tire Height	Rearend Ratio	Trans Ratio	MPH		Conv Slip%
Enter the RPM, Tire Height in inches, The Rearend Gear Ratio, the MPH, the Transmission top gear ratio and Click on Calculate...
Conv Slip% = [((RPM * Tire Height) / (Rearend Ratio * Trans Ratio * MPH * 336)) -1] * 100

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¼ Mile MPH Calculator
Tire Height	Rearend Ratio	RPM	Trans Ratio	Conv Slip%		MPH
Enter the Tire Height in inches, The Rearend Gear Ratio, the RPM, the Transmission top gear ratio, Conv Slip% and Click on Calculate...
MPH = (RPM * Tire Height) / (Rearend Ratio * 336.136 * Trans Ratio * Conv Slip%)

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Optimum Rearend Ratio Calculator
Tire Height	MPH	RPM	Trans Ratio	Conv Slip%		Rearend Ratio
Enter the Tire Height in inches, The ¼ Mile MPH, the RPM, the Transmission top gear ratio Conv Slip% and Click on Calculate...
Rearend Ratio = (RPM * Tire Height) / MPH * 336.136 * Trans Ratio * Conv Slip%)

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¼ Mile RPM Calculator
Tire Height	Rearend Ratio	MPH	Trans Ratio	Conv Slip%		RPM
Enter the Tire Height in inches, The Rearend Gear Ratio, the ¼ Mile MPH, the Transmission top gear ratio Conv Slip% and Click on Calculate...
RPM = (Rearend Ratio * MPH * 336.136 * Trans Ratio * Conv Slip%) / Tire Height

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Optimum Tire Height Calculator
Rearend Ratio	MPH	RPM	Trans Ratio	Conv Slip%		Tire Height
Enter the Rearend Gear Ratio, the ¼ Mile MPH, the RPM, the Transmission top gear ratio, Conv Slip% and Click on Calculate...
Tire Height = (Rearend Ratio * MPH * 336.136 * Trans Ratio * Conv Slip%) / RPM

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Engine Displacement Calculator
Bore	Stroke	# of Cylinders			Displacement
Enter the Bore in inches, the stroke in inches, the number of cylinders, and Click on Calculate...
Displacement = (Bore / 2) ^2 * PI * Stroke * # of cylinders

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Tire Height & Width Calculator
Tire Width (mm)	Aspect Ratio (1-100)	Wheel Diameter (in)		Tire Height (in)	Tire Width (in)
Enter the tire width in millimeters, the aspect ratio, the wheel diameter in inches, and Click on Calculate...
Tire Height(in) = (Width(mm) / 25.4 * Aspect Ratio / 100 * 2) + Wheel diameter Tire Width(in) = Width(mm) / 25.4

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Tire Width & Aspect Ratio Calculator
Tire Height (in)	Tire Width (in)	Wheel Diameter (in)		Tire Width (mm)	Aspect Ratio (1-100)
Enter the tire height in inches, the tire width in inches, the wheel diameter in inches, and Click on Calculate...
Tire Width(mm) = Tire Width(in) * 25.4 Aspect Ratio = (Tire Height - Wheel Diameter) / 2 / Tire Width * 100

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Effective & Equivalent Gear Ratio Calculator
New Tire Height	Old Tire Height	Original Ratio			Effective Ratio	Equivalent Ratio
Enter the New tire height, Old tire height, and the original rear gear ratio. Click on Calculate...
Effective Ratio = (Old tire height / New tire height) * Original ratio
Equivalent Ratio = (New tire height / Old tire height) * Original ratio

Engine Air Capacity & Carburetor Size Calculator (normally aspirated)
Displacement (in3)	Max. RPM			Theoretical Capacity CFM	Street Carb. Size CFM	Racing Carb. Size CFM
Enter the engine size and maximum RPM Click on Calculate...
Theoretical CFM = (Displacement * RPM) / 3456 Street Carb. CFM = ((Displacement * RPM) / 3456) * 0.85 Race Carb. CFM = ((Displacement * RPM) / 3456) * 1.1

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