Registration for the 2022 25 Hours of Thunderhill has opened. All teams interested in taking part in the longest closed-course endurance race in North America now can register using a brand-new registration process.

If you don’t know which class to enter, please refer to the NASA rules, and series rules, all available at: If you still don’t know where to class your car, please submit a support request. All racers must have their annual tech completed along with car classification forms and dyno certification forms, if required, submitted here.

As previously noted in Speed News, entry fees remain the same as years past. If you have any questions, please direct them to the NASA NorCal Region.

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