I ran a Heath h/o pump thru tank sock and a Racor 10 micron, and it held it's own most of the time, except WOT and heavy tow WOT, until pump caught up to the steady state demand about 2-10 sec, even a stock GM lift would do it but took forever to recover 20+ sec depending on the size of the hill or how hard WOT I was into it, and then just holding to 1 psi (minimum you really want as sustained IP feed), the Heath h/o holds 3-4 psi after recovery. Walbro never goes below 4 in any situation encountered thus far, 6-7 at cruise speed, 10-12 pulsed at idle.
Thanks, great info.