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Calculator For Figuring Choke Point Of Ports
Todays date is 2/22/2025
Enter your Minimum Cross Sectional Area (CA) of your Intake Port
CA equals the minimum cross sectional area of your intake port. (length times width)
This is most times your push rod area, but not always.
CA:
Bore:
Stroke:
Input you Bore/Stroke and CA please
To Figure Your Minimum Cross Sectional Area (CA) of your Rectangular Intake Port
Make all measurements in
inches,
and convert fractions to decimal numbers.
Examples:
1-1/4 = 1.25
2-3/16 = 2.1875
>>
>>
(1
4) + 1
(3
16) + 2
Rectangular/Square runners
To calculate the cross-sectional area of rectangular and square runner profiles, measure the width and the height of the runner, and multiply the two together.
Measure in
inches!
Runner width:
Runner height:
Runner Area:
square inches (calculated)
Area = Width X Height
To measure Round Ports
Round runners
To calculate the cross-sectional area of round runners, measure the diameter of the runner, divide by two, multiply the result by itself, then multiply that by 3.14.
Measure in
inches!
Runner diameter:
Runner Area:
sq inches (calculated)
Area = (Diameter
2)
2
X 3.14
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