Does this sound crazy??
:confused: The fuel pump Holley PN 12-327-11 (110 gph) was reading 8.5 to 9 psi on the gauge. So I installed a pressure regulator Holley PN 12-803-1. It looked like it was set to about 6 psi from the factory so I left it set there to see how it performed. I have a Holley 750 vac sec carb that I've modified a little with bigger needle & seats, sec metering plate was replaced with the one you can change the jets in, (with no power valve or pump).
After a day or so it started pumping oil all over the pass side of the eng. It looks like it's maybe coming out of the top of the fuel pump.
Do I need this regulator??
Is the 8.5 – 9 psi to high for this carb??
Has this damaged the fuel pump??
Any suggestions please.
And Thanks for any here in advance.

Bob

I had the same experience with Holley & Carter "two piece" pumps that have the screws around the edge. Dumped them in favor of a crimped AC. Works great, no leaks. If it was good enough for a LS-6, its good enough for my lowly 396 auto.

Sounds like the pump diaphragm is gone. They can be rebuilt.