Car struggles to make fuel pressure

Mitco39

I have a CJM stage 1 return kit on the car running a fair amount of fuel (13psi of boost). I have started to notice that when the tank gets down below half it really struggles to make even set psi on the regulator; have it set at 56-58 PSI at idle and the boost is hooked up so that it should be in the high 60's under boost. But as the fuel level goes down it really struggles and even drops down into the 40s and the car misfires.

I have a 255 in the tank which from what I have read and been told this should be enough and in most cases it is when the tank is full. It also seems to be related to heat, maybe because the fuel pump is not fully sitting in the fuel it is getting hot? The fuel pump has a dedicated power line running to the pump and a good ground.

Just looking for suggestions of things to check when I tear into her today.

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