Here is some info for the stock fuel system in the S12.
Fuel System Cut-Off Discharge Pressure: 64 PSI
Design Current: 4.7A
Fuel Flow w/ 12V: 25 Gallons (95LPH)
Fuel Pressure Regulator (FPR): 36.3 PSI
Here's a little vacuum-to-pressure comparison that will help you see how pressure varies based on intake vacuum.
Vacuum(inHg) PSI
0.00 37.0
5.00 33.0 - 35.0
10.00 31.0 - 32.0
15.00 29.0 - 30.0
20.00 26.0 - 28.0
Hopefully this info helps someone in the future if they don't happen to own an FSM or are to lazy to look it up lol