carter afb: fuel disappears?
Concur with the comment that today's fuel is made for EFI and those still with carbs are stuck. I came to that conclusion ~20 years ago when driving the carb'd car (AFB and several different Holley's). Really wouldn't surprise me if the ethanol is aiding and abetting in making this even worse.
This is why I think that duplicating the EFI fuel system, as much as possible, is worth doing. Increase the supply pressure with an EFI pump mounted either in the tank or close to it and down low. Use a bypass type fuel pressure regulator (FPR) with a return back to the tank. If I were staying with a carb my by-passing FPR would be a whole lot closer to the carb than it is now, make the line from the FPR to the carb as short as possible..