It's probably fuel draining out of the float bowl. My Quadrajet does this. It's only a small amount and makes the engine a little rich on a hot start. Leaning out the idle mixture screws no more than 1/4 to 1/2 of a turn should help the car start more quickly on a hot start, but it will start more slowly on a cold start. My engine was starting so quickly on a cold start that the oil pump couldn't get oil to the bearings in time so I leaned out the idle a bit and it also sped up the hot starts.