Quote:

My holley black is not enough on my car.
About 520 hp 408 4 speed 3.73 3780 lbs.
It quits at about 5700 rpms in forth.
Stock type pick up but 1/2" to 1/2" alu line to filter then an8 to reg then two an6.




I suspect your issue isn't the fuel pump.
I ran a Holley black on my 422 small block for years( 650 ish horse) 9.80's at 3350 pounds at 7300-7500 every pass.
Swapped to a much bigger system and saw nothing, zero difference.
At 520 horse a blue should even likely be adequate.
Could be filter, pickup, voltage, regulator...... But that pump should be plenty adequate


69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight
418 BPE factory replacement headed stroker, 565 lift solid cam
Best so far, low 10.30’s 1/4
1.41 best 60 foot
6.56 at 104.17