Is it because people are raising pressure and are trying to compensate? I'm looking around to see what size pumps I may need and I did some math. A setup with 450 injectors at normal pressure would only require 110lph at the BARE minimum. So why 255lph??? That's like 1000cc injectors!!! I know you guys can't be running injectors this big. So what's the reason that I'm not seeing? I just want to know so I know what features to look for in a pump and why I need them.

 

well if you're running an FMU you need a high pressure pump, that's the reason for everyone running the Bosch pumps.

 

As boost increases so does the fuel PSI. Even with a static 1:1 fpr's this increase will be seen but not as much as rising rate fpr's.

 

It is tough to have too much fuel when you're dealing with FI of any kind, especially boosting high with a turbo. A good fuel pump is usually a must-upgrade when running FI.