Mechanical fuel pumps

I bought that Carter. Mostly stock HP 360,Thermoquad,still had fuel starvation at high rpm. Installed a electric pump at tank 4-7 psi to push fuel to the mechanical pump. It helped. No regulators.Fuel pressure is about 5-6 psi at carb. I also checked inside of thank,changed all hoses and blew out fuel lines.Just a thought.