Holley/Demon Carb stumble

Yup at 6 psi first gal 55 sec 2nt gal 52 sec later 3d gal, another 55 sec later and the final gal took 51 sec.
Average =52.75 Seconds per gal

Yes i would have to raise the psi on the regulator to get a apples to apples comparison between 6 and 9 psi flow.

This is the pump i'm running.
Walbro High-Pressure Inline Fuel Pumps GSL392BX