Todays date is 11/18/2018

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.

Input you Bore/Stroke and CA please

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 |