🏆 IN-SEASON CHALLENGE ROUND 2: The bracket field has narrowed to 16. The headliner is the Hendrick Civil War: Kyle Larson vs. William Byron. Why? Top-seed Tyler Reddick was eliminated at Sonoma. So What? Expect crew chiefs like Rudy Fugle (Byron) to potentially abandon macro race strategy for aggressive short-pit windows to ensure Byron clears Larson's bracket position.
Tech Section: The 670 HP Aero & Suspension Challenge
Chicagoland Speedway is a 1.5-mile intermediate oval that has weathered and cured for seven years without consistent stock car traffic. This return introduces a unique mechanical "wildcard" for the Next-Gen platform.
Package & Horsepower Logic: Teams are running the standard 670 HP intermediate package (358 cubic inch V8 with targeted tapered spacer). Why? This is distinct from the 750 HP package used on road courses and short tracks. So What? At Chicagoland, the rough surface acts as a "natural restrictor plate." Drivers must feather the throttle extensively, making mechanical grip and throttle control far more critical than raw aerodynamic drafting.
The Turn 4 Trap: Turn 4 features severe, weathered asphalt ripples. Why? Surface settling over a seven-year racing hiatus. So What? If engineers set the Öhlins TTR coil-over dampers too low to seal the underbody aero, hitting these ripples will lift the 18-inch wheels off the pavement, triggering instant snap-loose conditions at 180 mph.
Goodyear Technicals (D-5284 LS / D-5290 RS): This is the "Nashville Notebook" setup. Why? It was verified during an April test with Larson, Blaney, and Hamlin. So What? The curved backstretch keeps cars under near-constant load; if teams gamble on aggressive left-front camber, the sharp weathered bumps will cord the tire shoulders before the 35-lap fuel window closes.
Inflation Standards: Recommended minimums are LF: 20 psi, RF: 50 psi, LR: 22 psi, RR: 46 psi. So What? High RF pressure is mandatory to sustain the load of the unique continuous-curve backstretch.
The Turn 4 Trap: Turn 4 features severe, weathered asphalt ripples. Why? Surface settling over a seven-year racing hiatus. So What? If engineers set the Öhlins TTR coil-over dampers too low to seal the underbody aero, hitting these ripples will lift the 18-inch wheels off the pavement, triggering instant snap-loose conditions at 180 mph.
Goodyear Technicals (D-5284 LS / D-5290 RS): This is the "Nashville Notebook" setup. Why? It was verified during an April test with Larson, Blaney, and Hamlin. So What? The curved backstretch keeps cars under near-constant load; if teams gamble on aggressive left-front camber, the sharp weathered bumps will cord the tire shoulders before the 35-lap fuel window closes.
Inflation Standards: Recommended minimums are LF: 20 psi, RF: 50 psi, LR: 22 psi, RR: 46 psi. So What? High RF pressure is mandatory to sustain the load of the unique continuous-curve backstretch.
Entry List: Official 39-Car Matrix
| No. | Driver | Organization | Manufacturer | Sponsor |
|---|---|---|---|---|
| 1 | Ross Chastain | Trackhouse Racing | Chevrolet | Busch Light Flavor Showdown |
| 2 | Austin Cindric | Team Penske | Ford | PPG |
| 3 | Austin Dillon | Richard Childress Racing | Chevrolet | Dow Veterans |
| 4 | Noah Gragson | Front Row Motorsports | Ford | Long John Silver's |
| 5 | Kyle Larson | Hendrick Motorsports | Chevrolet | HendrickCars.com |
| 6 | Brad Keselowski | RFK Racing | Ford | TravelCenters of America |
| 7 | Daniel Suárez | Spire Motorsports | Chevrolet | Modo Casino |
| 9 | Chase Elliott | Hendrick Motorsports | Chevrolet | NAPA Auto Parts |
| 10 | Ty Dillon | Kaulig Racing | Chevrolet | Sea Best |
| 11 | Denny Hamlin | Joe Gibbs Racing | Toyota | Progressive Insurance |
| 12 | Ryan Blaney | Team Penske | Ford | Menards/Dutch Boy |
| 16 | AJ Allmendinger | Kaulig Racing | Chevrolet | Celsius |
| 17 | Chris Buescher | RFK Racing | Ford | Body Guard |
| 19 | Chase Briscoe | Joe Gibbs Racing | Toyota | Bass Pro Shops |
| 20 | Christopher Bell | Joe Gibbs Racing | Toyota | SAIA Freight + Logistics |
| 21 | Josh Berry | Wood Brothers Racing | Ford | eero |
| 22 | Joey Logano | Team Penske | Ford | Shell Pennzoil |
| 23 | Bubba Wallace | 23XI Racing | Toyota | Space Jam 30th Anniversary |
| 24 | William Byron | Hendrick Motorsports | Chevrolet | Anduril |
| 33 | Austin Hill (i) | Richard Childress Racing | Chevrolet | zone x 7-Eleven |
| 34 | Todd Gilliland | Front Row Motorsports | Ford | gener8tor |
| 35 | Riley Herbst | 23XI Racing | Toyota | Monster Energy Zero Sugar |
| 38 | Zane Smith | Front Row Motorsports | Ford | Vermeer Midwest |
| 41 | Cole Custer | Haas Factory Team | Chevrolet | Haas/Andy's |
| 42 | John Hunter Nemechek | LEGACY MOTOR CLUB | Toyota | Dollar Tree |
| 43 | Erik Jones | LEGACY MOTOR CLUB | Toyota | AdventHealth |
| 44 | JJ Yeley (i) | NY Racing Team | Chevrolet | Open Entry |
| 45 | Tyler Reddick | 23XI Racing | Toyota | Jordan Brand |
| 47 | Ricky Stenhouse Jr. | Hyak Motorsports | Chevrolet | Pylon Aviation |
| 48 | Alex Bowman | Hendrick Motorsports | Chevrolet | Ally |
| 51 | Cody Ware | Rick Ware Racing | Chevrolet | Super.com / Rocket Doctor |
| 54 | Ty Gibbs | Joe Gibbs Racing | Toyota | Monster Energy |
| 60 | Ryan Preece | RFK Racing | Ford | Athletic Brewing |
| 66 | Josh Bilicki (i) | Garage 66 | Ford | Open Entry |
| 67 | Corey Heim (i) | 23XI Racing | Toyota | Shield AI (Open) |
| 71 | Michael McDowell | Spire Motorsports | Chevrolet | Veterans 1001 |
| 77 | Carson Hocevar | Spire Motorsports | Chevrolet | Zeigler Auto Group |
| 88 | Connor Zilisch | Trackhouse Racing | Chevrolet | Red Bull |
| 97 | Shane Van Gisbergen | Trackhouse Racing | Chevrolet | SuperFile x Lefty Out There |