Need help

Ok so i finally got 42lb injectors and a pro m 80mm maf,did have 30lbers with FMU and 255 pump, having some issues, If im driving along in 5th gear or anygear and leave offf the throttle for a while the car sputters and then clears out wen i rev it, also if it shuts off I have to floor it to restart it, I have the fuel psi set at 42, and I left the FMU on because i dont have a recalibrated disc for it ,i did remove it and boosted the fuel press to 60 and it didnt run nearly as strong and it was leaning out so i didnt get on it too much It feels like i gained hp at higher rpm tho leaving the fmu and 42psi, any help with the fuel pressure? and I keep reading to remove the FMU but im scared to lean it out and it doesnt run as good. what would be best, Do I just need a tune or what?

yeah I think im going to get the fmu recalibrated for now and lower the fuel pressure...i cant get it any lower than about 42psi, i must need a different regulator,its the third one and the same problem,I had the car dynod about 2 years ago with 30lb injectors and less done to the car and it made 480rwhp and the guy told me my injectors are 100% maxed, he also told me it would blow up if he ran it the way i brought it to him, funny thing is I drove it like that with no probs at all, so when he tuned my chip and when i picked the car up and drove it, it ran like **** with only 420 hp and i told him about it so i left it another day and he put the fmu back on the car, that he took off without telling me,and the car made the 480 hp so i go and pick it up and it ran ok but not as good as it did with no tune so when i got home, out with the chip and back to the stock tune....i wasted about 500 bucks on nothing I was and still am pissed.