Now keep in mind each car is different so what works for me may not work for you. I used the 2.72 disk/ring combo, silver (long) spring and adjusted my FP down to 27 psi.(Some say 20psi some say 35-37. It all depends on what your car/setup is like). Under boost, FP for me went from 27 to 50-55. Your fuel pressure will vary depending on how much boost you are planning to run. Read these links here and hopefully they can help you out like they helped me out a lot with my fuel management problems. Good luck