73 camaro has a 5.3 241 heads btr truck cam, -8 feed line, aem inline 400lph pump,hyper fuel adjustable reg, fuel cell, stock injectors. Runs fine but after about 5 min of running it looses pressure under throttle. Pressure is at 60psi and when acting up can snap throttle and will drop to 40 and if you snap it again it'll drop to around 20. I replaced the pump, it had stick fuel rails and regulator and replaced the rails with summit rails and hyper fuel adjustable regulator and still same issue, it has 13.3 volts at the pump even when it drops pressure I'm lost can anyone drop some suggestions.

I have a filter right before the pump and it's clean, it's a summit filter with replaceable screen.

Yes it is, I think I may have found the cause I had just checked and cleaned the filter right before I installed the fuel cell, I pulled it off just to look again and there was plastic strands I guess from where they drilled the holes for the fittings. I cleaned it out and so far it seems good, hooding that's all it was.

It's a 40 the pump says to use a 100 but I figured that might cause alittle restriction but I didn't think the 40 would. But after cleaning it, it seems to be good now, still finishing stuff on the tune and the car so it's not on the road yet to find out for sure.