Header theory

[Nova-Mann]

In the process of designing my own stainless steel headers that would allow slightly more than .050" clearance when driving over a cigarette butt, I realized I was wowfully short of technical theory and data when it came to what I call the 4-2-1 style header.

In a full length header system your pulses are separated by 270 deg., then 180 deg., then 90 deg., then 180 deg., 270, 180,------. In a 4-2-1 system the first stage is 450, 270, 450, 270,------. The second stage is wierd.

I guess what I can't picture is:

1) How the scavenge effect works in the 4-2-1 system.
2) How this affects tube size and length in the primary and secondary sections.
3) How a 4-2-1 compares to a set of shorty headers (not block huggers).

Anyone done any research on this or know of a thread that can shed light on this issue? Bad headers can negate a lot of things done right in the engine department.