Unofficial speeds from organizational Next Gen testing for the NASCAR Cup Series on Jan. 25-26 at Phoenix Raceway. Note that times are unofficial, with no technical inspection conducted before each session.
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Day 1 – Practice
| Pos. | No. | Driver(s) | Make | Team | Best time (seconds) | Differential | Best speed (mph) |
| 1 | 5 | Kyle Larson | Chevrolet | Hendrick Motorsports | 27.329 | 131.728 | |
| 2 | 8 | Tyler Reddick | Chevrolet | Richard Childress Racing | 27.474 | -0.145 | 131.033 |
| 3 | 22 | Joey Logano | Ford | Team Penske | 27.500 | -0.171 | 130.909 |
| 4 | 47 | Ricky Stenhouse Jr. | Chevrolet | JTG Daugherty Racing | 27.534 | -0.205 | 130.747 |
| 5 | 23 | Kurt Busch/Bubba Wallace | Ford | 23XI Racing | 27.563 | -0.234 | 130.610 |
| 6 | 12 | Ryan Blaney | Ford | Team Penske | 27.583 | -0.254 | 130.515 |
| 7 | 17 | Chris Buescher | Ford | RFK Racing | 27.592 | -0.263 | 130.473 |
| 8 | 9 | Chase Elliott | Chevrolet | Hendrick Motorsports | 27.611 | -0.282 | 130.383 |
| 9 | 4 | Kevin Harvick | Ford | Stewart-Haas Racing | 27.648 | -0.319 | 130.208 |
| 10 | 18 | Kyle Busch | Toyota | Joe Gibbs Racing | 27.743 | -0.414 | 129.762 |
| 11 | 1 | Daniel Suarez | Chevrolet | Trackhouse Racing | 27.781 | -0.452 | 129.585 |
| 12 | 19 | Martin Truex Jr. | Toyota | Joe Gibbs Racing | 27.784 | -0.455 | 129.571 |
| 13 | 14 | Chase Briscoe | Ford | Stewart-Haas Racing | 27.809 | -0.480 | 129.454 |
| 14 | 31 | Daniel Hemric | Chevrolet | Kaulig Racing | 27.848 | -0.519 | 129.273 |
| 15 | 21 | Austin Cindric | Ford | Wood Brothers Racing | 27.894 | -0.565 | 129.060 |
| 16 | 38 | Michael McDowell | Ford | Front Row Motorsports | 28.004 | -0.675 | 128.553 |
| 17 | 42 | Ty Dillon | Chevrolet | Petty GMS Motorsports | 28.147 | -0.818 | 127.900 |
| 18 | 27 | Loris Hezemans | Ford | Team Hezeberg | 28.721 | -1.392 | 125.344 |
Day 2 – Practice
| Pos. | No. | Driver(s) | Make | Team | Best time (seconds) | Differential | Best speed (mph) |
| 1 | 12 | Ryan Blaney | Ford | Team Penske | 27.292 | 131.907 | |
| 2 | 22 | Joey Logano | Ford | Team Penske | 27.327 | -0.035 | 131.738 |
| 3 | 14 | Chase Briscoe | Ford | Stewart-Haas Racing | 27.376 | -0.084 | 131.502 |
| 4 | 9 | Chase Elliot | Chevrolet | Hendrick Motorsports | 27.413 | -0.121 | 131.325 |
| 5 | 4 | Kevin Harvick | Ford | Stewart-Haas Racing | 27.457 | -0.165 | 131.114 |
| 6 | 19 | Martin Truex Jr. | Toyota | Joe Gibbs Racing | 27.481 | -0.189 | 131.000 |
| 7 | 38 | Todd Gilliland | Ford | Front Row Motorsports | 27.594 | -0.302 | 130.463 |
| 8 | 5 | Kyle Larson | Chevrolet | Hendrick Motorsports | 27.607 | -0.315 | 130.402 |
| 9 | 1 | Ross Chastain | Chevrolet | Trackhouse Racing | 27.641 | -0.349 | 130.241 |
| 10 | 18 | Kyle Busch | Toyota | Joe Gibbs Racing | 27.645 | -0.353 | 130.222 |
| 11 | 17 | Brad Keselowski | Ford | RFK Racing | 27.688 | -0.396 | 130.020 |
| 12 | 23 | Bubba Wallace/Kurt Busch | Toyota | 23XI Racing | 27.705 | -0.413 | 129.940 |
| 13 | 21 | Harrison Burton | Ford | Wood Brothers Racing | 27.713 | -0.421 | 129.903 |
| 14 | 31 | Justin Haley | Chevrolet | Kaulig Racing | 27.748 | -0.456 | 129.739 |
| 15 | 42 | Ty Dillon | Chevrolet | Petty GMS Motorsports | 27.781 | -0.489 | 129.585 |
| 16 | 8 | Austin Dillon | Chevrolet | Richard Childress Racing | 27.786 | -0.494 | 129.562 |
| 17 | 47 | Ricky Stenhouse Jr. | Chevrolet | JTG Daugherty Racing | 27.826 | -0.534 | 129.375 |
| 18 | 27 | Loris Hezemans | Ford | Team Hezeberg | 27.928 | -0.636 | 128.903 |