Try this test: Drive the car the way you usually would. Immediately after shut-off, open the hood, remove the air cleaner allowing an open view of the carb throats. Watch and wait, generally only 2-3 minutes. If there is percolation, you will see fuel bubbling up and into the throats. This will flood the engine for the next start. I suggest a phenolic carb spacer, also called heat soak spacer. Search Ebay for one to fit your carb. Good luck.
