New toys... but i still need some help!

[240SxTYLE]

So i've searched and tried to read up on some stuff but i cant really find the answers im looking for. I'm not an expert by any means, but im trying to learn (which should be the important thing)... It seems to me that the more i read the more i find contradicting statements and since i started my love for 240s here i was hoping i could come back and get some help before i put my new toys in.

My current setup:
Redtop sr20, 3 in'' turbo back, greddy fmic, type s bov, and profec b.

new toys:
hks gt2510, hks actuator, tomei 550cc's, and an s-afc, z32 maf

statements of contridiction that i need dispelled:
I've heard that
1. 550's will not supply me enough fuel if i push 15psi or if im shooting for over 300hp.
2. afc's lose efficiancy after 15psi

If i can run over 15psi, whats the max i can run? what numbers could hp/tq numbers could i expect? I hope im not wasting anyones time with this thread, but im still learning and need help. any help would be greatly appreciated. thanks

Jayson