The opening practice for the Sonoma Toyota / Save Mart 350 set the stage for a competitive weekend, with drivers navigating the winding 2.52‑mile road course in California's wine country.
Key Takeaways from Group 1
Shane van Gisbergen topped the timing sheets with the fastest overall speed and the leading 5‑lap average in Group 1, yet the New Zealander was quick to voice concerns about a loose wheel and an overall dissatisfied feeling with his car's balance.
Not far behind, William Byron posted the second‑best overall speed and 5‑lap average, and claimed the top 10‑lap figure, while also praising the ride quality of his machine, suggesting a strong setup for the race.
Connor Zilisch impressed with the fourth‑quickest overall speed and a third‑best 5‑lap average, but he reported a lack of rear grip and tire wear that could affect his long‑run pace.
Christopher Bell, who intends to run the full event, logged the eighth‑best 5‑lap average and also mentioned a loose wheel, highlighting another area of focus for his team.
Erik Jones endured a turbulent session, completing two off‑road excursions that resulted in visible damage to his car, underscoring the challenges of the Sonoma layout.
With several drivers flagging mechanical concerns and the track demanding precision, teams will need to fine‑tune their setups before the final qualifying runs and the main race on Sunday.