The Royals (38-32) entered the day just 0.5 games behind the Tigers in the division. They were able to flip standings with tonight's win to move into first place for the first time in June since 2003.
Detroit's Max Scherzer had won ten home starts in a row, but surrendered a season-high 10 earned runs Tuesday night.
Alex Gordon and Mike Moustakas kick started the Kansas City offense in the second inning as each hit a two-run home run.
Omar Infante drove in two more on a single, and one for Eric Hosmer on a ground out, as the Royals opened a 7-0 lead just two frames in.
Salvador Perez, Jarrod Dyson and Lorenzo Cain also added RBI singles later in the game as Kansas City reached 11 runs in consecutive games for the first time since 2001.
Yordano Ventura held his own on the mound in the win. The rookie allowed three earned runs through seven innings while striking out four in his fifth win of the season.
With two wins to start the four game set, Kansas City can do no worse than a series split. Game three is coming at 12:08pm Wednesday afternoon.