I have been fighting this issue for a long time and have not resolved it yet. If anyone has had the same experience and resolved it I would love to hear from you! When the car starts to warm up the fuel pressure starts to drop. The regulator (replaced twice with no effect) is adjusted to 7.5 psi cold and once the car reaches a temp of 180 degrees or hotter the pressure drops to about 2 psi. I have a mechanical fuel pump (1st one was Holley Volumax 170 gals/hr at 15 psi) (2nd one is Elderbrock 130 gal/hr at 12 psi) with 3/8” SS lines (pre-bent) coming from the fuel tank. I have #6 fuel line going to the carb. I have bypassed the gas tank and lines by running a separate, short 3/8 fuel line from a gas can to the inlet of the fuel pump with no improvement. I have ran cold water on the fuel pump, regulator and fuel lines to include to gas tank with no effect. All rubber transition lines have been replaced. All lines have been wraped with insulation to keep the radiant heat off them. The car is starving for fuel at 6000 rpm? Help!