I never really check the fuel pressure from a stock mechanical.
I believe NOS wanted 6psi for there nitrous system @ all times.
I would think the stock pump would not provide that (6psi) off of idle or low RPM.
There are billet type fuel pump that are quiet that put out 6 psi. The Holly's (red & blue) are pretty loud.
I know the Mallory billet low presure fuel pumps are quiet until you step up to the higher psi pumps.
I would think the other brands low psi billet pumps would also be quiet.
