No Fuel Pressure

I have a wierd problem, The car starts fine then over about 5 min's you can watch the fuel pressure slowly drop from 6 psi to 0. I have changed the fuel line to a 3/8 line and I know there are no kinks, I just changed the fuel pump to a new Carter HP, I have removed the fuel pick up from the tank and made sure there were no problems with the inlet. I have blowen air threw the line from the front to the back and all is clear. The fuel filter is clean. the only thing I can thik of that I haven't looked at is the accentric on the front of the cam but I have never heard of that failing. What else is there? Has anyone seen this before?

The motor will still run but only at idle. I just put a gas can at the rear of the car and unhooked the fuel line from the tank, placed a long rubber hose on the fuel line and put the other end into the gas can to rule out any in tank problems. Same result. This is a factory 3/8 pre bent fuel line and the car ran fine for about a year. I can't believe it just started to vapor lock out of the blue.