Parker Bowles added two goals for the Americans (26-16-3), while defenceman Drydn Dow and leading scorer Justin Feser each finished with a goal and two assists.
Brian Williams and Mitch Topping rounded out the scoring for Tri-City, which went 2 for 3 on the power-play.
Travis McEvoy had a goal and two assists for Vancouver (12-33-0). Tristan Sieben, Thomas Foster, Luca Leone and Dalton Sward also scored for the Giants, who were 1 for 6 with the extra man.
Americans goaltender Luke Lee-Knight gave up three goals on 15 shots, while teammate Troy Trombley allowed two goals on nine shots.
Vancouver starter Jared Rathjen stopped 11 of 17 shots in his two stints on the ice while Payton Lee stopped eight of 11 shots in just under 19 minutes.