Well, still sorting through a few issues.
First problem was with my alternator, I had installed a 200 amp alternator kit into my original alternator and replaced the rotor as well. When the truck is running the battery light was dimly lit, and the alternator was only charging at ~13.2 volts. I unplugged the regulator and the battery light when out (like it should), but the voltage jumped up to the mid 14's....WTF? How can alternator charge without a regulator? Called up the alternator company and they are shipping me out another regulator.
Second issue, and the one I need some help with.
The fuel pressure was bouncing around pretty violently with the new regulator, almost 20psi. My first though was that the regulator is simply too big and the poppet just cannot easily control pressure at a volume much lower than what it is rated for. I called up Fuelab and they said the pump will be fine under these conditions. I could have left it at that, but I could not take the sound the pump made.....it was so violent that the fuel lines were bouncing all over.
Aeromotive said its not the regulator or the pump.....its cavitation......huh?
Why does is only do it with this regulator and not the previous one?
This evening I had planned to put a piece of clear hose in the return line to verify, but I could not find any around the shop. Instead I plumbed in another regulator after the big one.....and bingo.....fuel pressure was silky smooth again.
This disproves the idea that the regulator is simply too big, or it would not change with the other regulator downstream.....or am I missing something?
So in the meantime I pulled the adjusting screw out of the big regulator and used the second regulator to pull the fuel pressure up to what it needs to be.
Any ideas or direction I should take to resolve this?
Check out this mess of lines........