Allmendinger posted an average lap speed of 102.187 mph early in the second 20-minute session.
Austin Cindric, who needs a strong finish or a win to advance in the series playoffs, ended up second-fastest (102.105 mph).
William Byron was third, Joey Logano was fourth and Daniel Suarez ended up fifth.
Group B
Allmendinger quickly set the fastest speed of the day early in the second session (102.187 mph).
Suarez was second (101.583 mph) and Cole Custer third (101.409 mph).
Ryan Blaney was fourth and Bubba Wallace rounded out the top-five.
In the opening laps, Ricky Stenhouse Jr. spun out between Turns 4 and 5 but was able to continue without an issue.
Late in the session, NASCAR was forced to display a caution for the stalled car of Conor Daly. Daly, making his Cup Series debut this weekend, hit the wall near the backstretch chicane.
“I just lost all steering,” Daly said after being released from the infield care center. “It just went straight into the wall. It was as if you just disconnected the steering entirely & I could have just rolled the steering wheel anywhere I wanted. So that was weird. I’ve never felt anything like that before in my life.”
Group A
Cindric led the way in the first 15-minute session with an average lap speed of 102.105 mph.
“It’s a start,” Cindric said. “Obviously we’ve got some pace but we still have to keep working at it. The track is probably going to change quite a bit. It’s still pretty green from just one Xfinity practice (today) on it.”
Byron ended up second (102.091 mph) and Logano was third (101.801 mph).
Kyle Larson was fourth and Tyler Reddick rounded out the top-five.
Larson missed the frontstretch chicane on early one lap, failed to come to a complete stop and had his time disallowed.
Reddick went off course in Turn 7 at one point but was able to continue on without an issue.
Corey LaJoie missed the frontstretch chicane late in the session and had to serve a stop-and-go penalty.