Those pressures sound OK to me, not sure what specifically the FRST fuel pressure is meant to be but my mate's mk2 rally car which runs 2x 45 DCOE's goes to about 4.5 bar when primed and then 2.75 when running. When you measured this pressure was the car running OK? You want to know what the prerssure is when the car isn't running OK to relate the running problem to the fuel pump. HTH