With pumps that provide a lot of pressure and volume your best bet is to set it at between 5.0 to 6.5 lbs. of pressure with the motor running at idle speed so you can get set like it will be running with at the track.
I've used from 4.0 to 9.5 lbs. of pressure on some of my old race cars before switching to one of the bigger, better high pressure and high volume pump like yours is now, my current S/P car has a front mounted fuel cell with a BG 400 pump with a Magna Fuel 4 port regulator that is currently set at 5.5 lbs. with the motor idling at or above 1200 RPM running E 85 pump fuel, this combination works very well, 8.86 at 150.6 MPH in the 1/4 mile so far, soon to go faster
Monte Smith had advice many racers on this forum with the bigger race pumps to use between 4.5 to 6.0 lbs. while idling tp prevent the higher pressures to foam the fuel going into the fuel bowls
I listen and turn down my pressures on this car from 7.5 Lb. to 5.0 Lb. and saw no loss or gain in ET or MPH