Group A
Austin Cindric topped the charts among both Group A drivers and overall at 131.09mph, but it was Hendrick Motorsports who really impressed. William Byron was second in fastest single lap times in Group A and fourth overall, but led the way in the five and ten-lap averages.
They were followed by Chase Briscoe, Joey Logano and Chase Elliott.
"Our goal here was that if we unloaded pretty close, we were going to do a long run," Byron told FS1. "Luckily, we unloaded close and everything felt pretty good. We just kind of kept running laps to see where the resin comes in and kind of see how all that feels.
"(I) feel really good about my car. My Axalta Chevrolet feels great, and I've been doing a lot of short track racing lately, so I'm hoping that will help me this weekend."
Drivers were quick to migrate to the top grooves of each turn as they got a feel for the resin that was added to the track's surface, allowing for better runs through the center of the corner and exit.
"I'd say these things are driving like early 2000s Trucks," said former series champion Kurt Busch, who also called it a "fun challenge." He was seventh on the time charts in Group A.
Stewart-Haas Racing had to change the brakes on the No. 14 car of Chase Briscoe after a crack was found on the brake rotor.
The first part of the session went incident-free.
Group B
No driver in either group seemed too interested in cutting the dogleg on the frontstretch, which we've become accustomed to seeing at Phoenix. Teams are unsure how the cars will react to the bumpier apron and worried that the rear diffuser could be damaged.
Ryan Blaney led the way among Group B drivers, but he could not match his Team Penske teammate Cindric, falling 0.009s shy of the fastest time.
He was followed by Tyler Reddick, Kyle Larson, Ross Chastain and Kyle Busch.
Hendrick again showed the way in lap averages with Larson topping 15, 20, 25, and 30-lap averages.
Reddick, who has been battling leg numbness the last two weeks, appeared happy with the changes RCR made for him this weekend.
Ricky Stenhouse Jr.'s car was taken back to the garage after practice for an engine change. He will not take part in qualifying and will have to start from the rear of the field.
Group B's session also went incident-free.
