Holley eletric pump sometimes louder!! Like bad loud??

So, you are running a regulator without a return line? This is a great way to promote cavitation and vapor lock, as the pump cannot maintain a constant flow through the pump. If the pump is much larger than the engine requires this can be greatly aggravated.

Also, just pumping fuel heats it up. "Pumping losses."

Any chance something is restricting the inlet?