i'm not saying that you should EVER use someone else's numbers on your own car, as every motor operates differently. however, on 550cc injectors, and a lex AFM/ maft unit, you should be running the BASE fuel pressure lower than the stock setting. i'm not going to give you a number, but think of how rich we run stock, and how much MORE rich we run with a lex/maft + 550's.
you need to experiment with a wideband and figure this out for yourself.
for reference: stock BASE fuel pressure is 40psi. base fuel pressure means that the vacuum line is DETACHED. (not pinched, actually removed and capped so the AFPR can get a reading from the atmosphere)
when the vacuum line is replaced, you're looking at a drop in fuel pressure by about 10psi on a healthy motor. (30psi w/ vacuum)
now, simply for reference sake- do not use these numbers. experiment for yourself:
my base fuel pressure with the mods listed in my profile is set at 32psi, and drops to about 22psi at idle with the vacuum line attached, and i'm still running rich throughout the powerband in every gear.
-shaeff
