NASCAR is preparing to roll out a new rules package for the upcoming Daytona International Speedway event scheduled for August 29, a race that will determine the final 16‑driver lineup for the 2026 Chase for the championship.
Aerodynamic overhaul aims to reshape superspeedway racing
The package introduces a 4‑inch rear spoiler, wider splitter stuffers and a redesigned spoiler deflection device, along with new braces intended to alter the car’s aerodynamic balance.
Engine specifications will be trimmed to 465 horsepower, down from the 510‑520 horsepower range used on superspeedways this season, and the tapered spacer on the engine will be reduced to 27/32‑inch, further limiting power output.
NASCAR’s data suggests that these changes will make passing easier and could add roughly 2‑3 miles per hour to single‑car speeds during qualifying, while draft speeds are expected to remain comparable to previous configurations.
The modifications are being tested for the first time in a competitive setting, as there is no practice session scheduled before the race, meaning drivers will experience the new aerodynamic behavior under race conditions.
Although the package is not guaranteed beyond this event, it forms part of a broader effort to address longstanding drafting issues, such as the difficulty of forming a third lane, and to inject fresh competitive dynamics into the season‑ending superspeedway races, the next of which is at Talladega on October 25.
Safety elements such as the A‑post flap will remain unchanged, preserving the series’ focus on driver protection while experimenting with performance adjustments.