I mentioned above a procedure for measuring port centerline length by Larry Meaux the author
of Pipemax, below is that procedure. First you will need some 1/8 inch pin stripping tape. The
photos a pretty much explain themselves.
It takes two runs of tape along the short side radius and the long side radius. Mark the tape at both
ends. Remove the tape and place in a straight line on a flat surface to be measured. After you get both
measurements, add them together and divide by 2 to get the Centerline length.
These measurements will be used to make a calculation that is Critical to Pipemax. The calculated
values below will be input into Pipemax in the Yellow fields. First are the measurements input into
the Excel table. I took lots of extra measurements.
Now the calculations. The yellow values go directly into Pipemax.
Copied from Pipemax is the formula used in the Excel table below.
Calculate the CSA Velocity FPS by measuring the Head's Intake Port CenterLine Length , then measure the Intake Port Volume CC's,
****** CSA Velocity FPS = ( Intake Port CFM * Intake Port CenterLine Length * 39.3289536 ) / Intake Port Volume CC
BTW I took more measurement than what's needed for Pipemax, didn't want to find out I needed
something later and then couldn't get to it to measure. Since the exhaust port exit is not square or
round, I traced it onto graph paper to get the port cross sectional area.
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