That would make sense. With there being a "vent" port on the regulator I can see where it would be sensing atmospheric pressures and not MAP. So, I guess it's back to the drawing board with regards to my plumbing plan. LOL!!
This next question may be aimed a little more at Ross and the Borla regulator he uses. In the Borla reference material it specifically says to install the regulator on the downstream/return side of the fuel rail. So, the question is, is it acceptable to have everything (fuel supply from pumps, fuel rail distribution lines, and fuel pressure regulator) all plumbed into a single fuel log/distribution block?
Mark
We plumb the reg on the downstream side of fuel block which is either rear baffle or engine spine mounted.
This photo shows the 6 cylinder spine mount block. Fuel pump connects to one end fitting, regulator to the other end.
We use the Borla regulators exclusively as they have a dual Viton diaphragm and are made in the US. Too many other brands are built offshore these days (even some famous US brands) with inferior materials and design to save money. This is something which demands best quality and not a place to save money in our view.