https://datazap.me/u/bradsm87/rev50?...0&zoom=231-300

I'm very disappointed to say the least that my rail pressure has fully crashed by 6500 at 17psi. I have some later logs where it even does it at 16psi. I'm only running E25. I've heard of plenty of people running 21+ psi on E40 without TBI or PI.

I've only ever heard of HPFPs failing with more noticeable issues such as long cranks and sudden fuel pressure drops. I don't have any such issues. Has anyone heard of HPFPs slowly wearing with the only symptom being a lower flow limit? I haven't.

LP fuel pressure on most of my logs is around 60psi at high RPM and load. If I go down the path of replacing the fuel filter in the hope to get the LP pressure higher, is that likely to help? I think of course it would but I hear time an time again that it's fine as long as it's over 50psi.

I'm at a point in my life where I truly, truly hate working on my cars. Nothing would be more frustrating to me than replacing things and finding out they did nothing to help.

Thoughts, findings or opinions?