I have a Profec B spec II and assuming thats what you have since you didnt specify weather its the 2 or 1. Anyhow the valve unit is important. The COM line goes to your wastegate actuator and the NO goes to a boost source(ona t25 it connects to the turbo, i have a EVO III 16G and The line that comes off my intake mani to the BOV I spliced and used it as my source. Everything works fine). Be sure the PC line has the plug off!!! The line on the fuel pressure regualtor you cut and splice a line to the back of the controller itself. Then it should work great. I have had no problems or complaints with it. Worth every penny!