At 05:41 PM 5/16/2012, Scott Daniel - Turbovans wrote:
>I can tell you for sure that if you're drivin' along at say 30psi a
>light throttle ..
>and you open the throttle a lot ..fuel pressure goes up,  a few psi.

It would have been clearer if I'd said that fuel pressure on your
gauge goes up because the manifold pressure has gone up (less
vacuum), and the regulator is maintaining a constant pressure
difference between the manifold and the fuel rail.  That means the
pressure difference between the fuel rail and the outside air will be higher.

When the fuel pump is running but the engine is not (no vacuum,
manifold pressure equals outside air pressure) the reading on your
gauge will be the actual pressure that the regulator is constantly
maintaining across the injectors.

Yours,
David