The car I drive most often (3-5 times a week) acts like you are describing. If I leave it sit over night after use it will fire right up. If it sits for two days you have to crank, pump crank, pump crank, pump and maybe one more crank and pump to get it to fire especially during winter months. This issue is completely resolved if I run 50% or more 110 race gas mixed with any variety of pump fuel. It's a stock 383 so it runs on 87-92 and personally I'm not so sure the ethanol free fuel is that good either. On straight pump fuel (any of the above) the fuel will percolate in the float bowls at shutdown if the engine is heat-soaked.

The best remedy is to toss five gallons of 110 in the tank now and again with the unleaded swill. Unfortunately that is fallacy of the "pump gas" craze in engine building...you build this killer engine with compression that will work with pump gas but then you are afraid to feed you new engine crap lol.

Personally I don't like cheap electric fuel pumps for reliability/QC reasons and don't want a quality pump buzzing away over the oem mufflers.