WN 3978 then DL 514 at Phoenix
Salt Lake City → Phoenix → Boston
Timetable, Phoenix time
06:45WN 3978 from Salt Lake City at the gate
23:23DL 514 to Boston leaves the gate
16 h 38 apart on the timetable
DL 514 leaves 16 h 38 after WN 3978 arrives on the timetable: more than half a day, so not a connection we count.