My lack of googling skill just hit me right between the eyes.

What is the longest drive/single drive with most yards?

With tfl, sacks and penalties, there's several ways to lose yards you have to regain. Has there ever been like a 140 yard drive?

Statistically speaking (including every game since 1999), it was 120 yards on this drive, led by the Giants' Kerry Collins in the 4th quarter of a November 19, 2000 game at home against the Lions. In 17 plays, the Giants gained 120 total yards (losing 40 due to penalty), with Collins racking up 117 yards passing.

here = http://i.imgur.com/OtaegFE.png

Rich Gannon also threw for 120 yards in a single drive in this game: https://www.pro-football-reference.com/boxscores/200409190rai.htm

Today, of course, Mahomes threw for 116 on the opening drive for KC.

Neat. That's actually a fair few more than I expected. Thanks!