There might not be a natural connection between these three elements. 'Pulp Fiction' is famous for its nonlinear narrative, memorable dialogues, and unique characters. '420' is mainly known in the context of a time reference in cannabis - related subcultures. 'Clocks' are a common object that can symbolize time or be used in various ways in different works. It's possible that someone could create an artificial connection, like making a piece of fan art where a character from 'Pulp Fiction' is standing next to a clock showing 4:20, but in the context of the movie itself, there doesn't seem to be an inherent link.