ok here's the situation i have a hrc kit w/450cc injectors and safc

i start the car and it says its running lean so i wait for the o2 sensor to warm up sometimes it idles very rough. my fuel pressure at idle is 20 psi (to adjust for the 450cc inj.) i start to drive and the car runs fine getting a rich reading but if i accel right between 3000 and 4000 it goes very lean and stumbles. could it also be the lo hi throttle setting mine is at 40% lo 50% hi. i have also heard a slight buzzing come from the fuel pump sometimes when this happens. i have the stock pump and the holley inline that came with the kit.
i don't know if it is fuel cut , a bad pump, bad o2 sensor or what.
i thought i would see if anyone else has had the same issues. also how do you adjust this damn cartech fmu for boost rising rate i have too much fuel even at 18psi. (how do you adjust the neddle valve)