The narrow end of the titanium inlet hole is at a higher psi than the wide end. It's like any nozzle psi goes up when flow area goes down. The way I see it is this creates a changed flow path at the exit plane of the inlet hole. Flow total is the same always. Fram graphics designers decided to make something of it, probably exaggerated, and draw the orange swirl on the box.
All the oil is at basically the same pressure in the cavity of the oil filter mount on the inlet side of the base plate holes - regardless of the base plate inlet holes shape. There is a pressure drop across the inlet holes of course. If the flow path of a fluid causes turbulent flow ("swirls") then that will actually increase the drag and delta-p through that turbulent flow path. So if Fram is claiming (they haven't, but people are imagining) that the oil somehow "swirls" through the filter like a tornado because of the tear dropped inlet holes then that would actually increase the flow resistance (and total delta-p) across the filter. But Fram is claiming the Titanium has "better flow" ... which just means those bigger inlet holes have more flow area and less delta-p. The whole "swirl to increase flow" is imagined and good marketing to sell oil filters.
