I've been driving for the last 15 years on elect fuel pumps. Ok.... Car sits,,, turn on the pumps,,,pump gas, and engine fires. I'm recently on my second car in last two months with mech pump(s). They both seem to starve for fuel if they sit for more than 2 days. Engine has to crank and I have to pump the gas like crazy in order for the engine to start. Do the mech pumps suck fuel out of carb bowl when sitting? These are both Edelbrock Carter AFB style. I've tried an Omega loop...no luck. Does anyone sell a fuel filter with a check valve??. This is driving me nuts..........