Penske’s Ryan Blaney topped the speed chart at ISM Raceway with an average lap speed of 141.716 mph – a speed that was markedly faster with the new aero package over the top speed in the first practice at this race last year (138.281 mph).
Blaney’s teammate, Brad Keselowski, ended up second-fastest (140.680 mph) and Kyle Larson was third (140.406 mph). Chase Elliott and Kyle Busch completed the top-five.
Rounding out the Top 10 were Jimmie Johnson, Alex Bowman, Erik Jones, Martin Truex Jr. and Matt DiBenedetto.
Nine-time Phoenix winner Kevin Harvick – who won this race a year ago – was 15th.
Compared to recent weeks, the aero package at Phoenix features higher horsepower and higher downforce.
Keselowski and Penske driver Joey Logano have won two of the season’s first three races (Atlanta and Las Vegas).
There were no on-track incidents in the session.