SHOdded said:IIRC, the HPFP maxes out around 2500 psi for gen 4, 3000 for gen 5. Injectors have never really been an issue re flow rates. But if you are pushing the envelope, can't hurt to upgrade.
FoMoCoSHO has pushed hard with Eblends for some time now, both gen 4 and 5, and has yet to upgrade the fuel system at all. More details, he will have to provide.
How good your tuner is ... That seems to be the limiting factor really.
I agree with this. Your tuner / AJP will max out what you have and keep the OEM Fuel pump pressure within its limits.
I have awesome 93, E30, and E85 tunes from him. I am sure the car can do more with more rail pressure but those new fuel pumps are out of my price range atm.