Why did Piper change from the overhead and door vents to the later floor vents? Having learned in Cessna 172s the wing vents were nice. However in my 1969 Cherokee 140 the floor vents don’t seem to cool you as good has the Cessna 172 vents. I have never flown an older Cherokee with the overhead or door vents but seems they would do better than the floor vents. If the answer is to decrease drag I would question what fraction of a percent of drag was reduced.