I dont know if the fact. FP Regulator is about to kick the bucket, but here are the symptoms.

Racetronix Intake Pump
New Fuel Filter

Under normal conditions- Idle is 62psi, WOT 66000 RPMS, PSI will drop to 50-52psi....

Now the idle psi will differ- it will sometimes idle as low as 56 or 58 psi and when this happens my WOT 6600 RPMS, PSI will drop t o 46-48 psi.

Usually when its warm out is when the car will idle at a lower psi and the consequential lower WOT psi, i've noticed b/c when its cold and the motor is started it will idle at 64 psi untill the motor warms up then drop to 62psi.

I've done searches and asked lots of people and no one has an answer?

 

sure, i would toss a regulator on it and see if it stabilizes. it is not uncommon (i had a bad one) BUT
-you could have a charging voltage problem at wide open, watch for steady voltage over 13v.
-you could have a clog at the inlet to the fuel pump, leaf etc in the tank
-you could have a split on the pressure line inside the tank, or a leak (use only fuel injection rated hose and non fuel corrosive clamps)
-you could have a wacky electrical gauge /bad ground, confirm with a mechanical gauge(free to buy, use and return from pep boys etc)
-you could have a kink in the factory plastic pressure line as it comes out of and down from the tank (i had one once)
-could have a mashed line under the car from a previous wreck or catching a rock (or curb )

since you have the racetronix kit i am ruling out a voltage drop problem between alternator and fuel pump

hope that helps

 

well i've determined that it only does this when its warm outside. the past 3 day's its been in the 80's and i've had the low fuel psi, but today its low 50's and its normal.

Thanks for the input Mighty Mouse, but damn thats alot of stuff to check !