There exists a minimal port area for each combination that meets your target for peak rpm.
With almost every cylinder head (or intake) this power limiting port area is the constriction between the push rods
(or the most limiting intake runner cross section).
CA equals the minimum cross sectional area of your intake port. (height times width)
Port velocity is good, but too much will limit power - completely independent of CFM numbers
CA calculator at bottom of page.
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Make all measurements in
inches,
and convert fractions to decimal numbers. Examples: |
||
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1-1/4 = 1.25
2-3/16 = 2.1875 |
>>
>> |
(1
4) + 1
(3
16) + 2
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