Whoa whoa whoa, the carb should not be dry after sitting a couple days. If it is, the carburetor is leaking fuel while it sits. Fuel drainback in the fuel lines will NOT siphon fuel out of the carburetor. The fuel inlet on the carb is at the top of the bowl not the bottom, so it would only suck air as the fuel drains back, the bowl would stay full of fuel.

Try this: Start the car and idle for just a couple minutes, THEN let it sit for a couple days and try starting again. If the problem is gone, then the cause must be fuel boiling out when the engine is hot when parked (I think it's very unlikely it would boil all the fuel out). If it starts hard like usual, you have a leaky carb, it's probably bleeding all the fuel out into the intake while sitting parked.

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'86 Bronco, 460, E4OD; '85 Ranger, 350hp 289, T5, 12.9@110.5
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