@Tmoose - The tests were all performed back to back on a dyno and the curves, peak hp/tq and AFRs were observed. The OEM size is 3.50", but is very short (and goes into an air box) and is corrugated which puts the effective inner diameter at 3.25". Each tube was tested with a 45 degree elbow...
@gruntguru - "Plenum ram tube" is how it's described in the book and in my opinion is appropriately names since the goal is to help fill the plenum as fast as possible.
@GregLocock - Interesting thought, I'll run some numbers and see what I get comparing runner area to intake tube area.
@hemi - Not sure if there is a principal, just trying to determine optimal tube diameter.
@gruntguru - The formula example given in the book was for a 4cyl and yes, I'm applying it to a V6 (obviously with my own numbers plugged in).
@TMoose - Both peak hp/tq as well as the curve. Yes, the...
To prove a theory that the aftermarket intake systems being sold were too large for one of my cars, I used the following formula
D = SQRT((CUI x VE x RPM) / (V x 1130))
which I found in the book, "How to Tune and Modify Automotive Engine Management Systems" by Jeff Hartman.
The math as I...
