As noted by many on this thread, your starting problems are more than likely the result of evaporation due to the Holley being vented,....I have mostly multicarbed cars running Holleys, when gas was good, yeah it could sit for weeks on end and start no problem, todays gas isn't even good for a week in a typical Holley fuel bowl it evaporates so fast, so rather than sit there winding the piss out of your car trying to start it, locate the tube vent on your Holley, and use a small squeeze bottle filled with gasoline to fill the bowl prior to starting, by filling the bowl thru the vent tube, 4 oz should fill it...


And it would be a good idea to set your fuel level/float, and/or confirm it's level...Holleys are the easiest carbs to tune/adjust/rebuild, get yourself a Holley tuning guide from HP Books and learn what you need to know...

Kere's one of the vents located on a Holley, connected to the primary fuel bowl