Fuel pressure erratic at all rpm-Help!

[YELLOW89']

My fuel pressure on my guage bounces from what it's set at down anywhere from 1-7 psi lower and then back again. It does not seem to be rpm dependant. Does it at idle most but even at wot it has some bounce. The fuel pressure guage actually is noisy it bounces so much!

300 hp NA car
1/2" intank pickup to big fuel filter to 255 lph INLINE pump to -8 to rail and then back with -6.

I had to set the pressure to 45 vac off otherwise it would hesitate at half to full throttle starting at 2000rpm. Help! It does pull good to 5500rpm but on the highway you can feel it hesitate slightly every few seconds.

I think the problem would be solved if I switced to a 255 INTANK pump and put the filter AFTER that. I was told the pump may not be holding pressure because of the -8 line.

This isn't normal right? What's the problem?