Nick Suzuki and Artturi Lehkonen each had a goal and an assist, and Carey Price made 27 saves for the Canadiens (6-1-2).
"I don't think there's any way that we can't play," said Petry, who also had an assist. "We can play a fast game, we can play a physical game, depending on what the other team throws at us. But there's one thing that we always rely on is our speed and I think it's hard for teams to come out and set the pace early. I think it's hard for teams to keep up with us for the full 60 minutes."
Adam Gaudette and Jay Beagle scored for Vancouver (6-6-0), which outscored its opponents 20-4 during the winning streak. Braden Holtby made 34 saves.
"We have guys that can work, guys that can play within a system, and if we have some guys not doing it and some guys doing it, it's not going to work very well," Holtby said. "And we've seen that in passing, that goes for any team. Against a team that wants to go and wants to pressure, the simpler the better. And we know that. Now we've just got to go execute it."
The teams close the two-game set in Montreal on Tuesday (7 p.m. ET; TSN2, RDS, SNP, NHL.TV).
After Suzuki put the Canadiens up 1-0 at 1:00 of the first period, Lehkonen made it 2-0 with Montreal's sixth shorthanded goal at 6:10.