Endurance racing is back at Thunderhill in 2026! Home to the original 25 Hours of Thunderhill, the NASA NorCal Region has announced it will host a 12-hour Team Racing Endurance Challenge event at Thunderhill Raceway Saturday, September 19, 2026.
The race will run during daylight hours, so there will be no need for lighting on the cars and probably only nominal lighting for crews. Free reservations for the event open January 2 with the entry fee due by March 31.
Entry fees will be $1,995 if paid by March 31. You can reserve your space starting January 2 at no cost, starting January 2, and take advantage of the early bird rate when you pay by March 31. After that date, entry fees will rise to $2,195.
There will be no other fees. It’s important to note the entry fee also will include the annual NASA membership fee, so drivers easily can return to participate in more events in any NASA region.
As mentioned in the rules, TREC racing is all about fun. There is no medical exam required to race, and the race is open to drivers of varying skill levels, including HPDE3 and up. Cars will run in lap-time-bracketed classes on 200 treadwear tires, and TREC racing rules have strict “no contact” provisions to keep things fun and entertaining.
NASA NorCal Regional Director Jerry Kunzman worked directly the management at Thunderhill Raceway to secure a date that would ensure teams could race without the need for lighting or foul-weather gear. The race also will take place after Thunderhill has competed a full repave using a contractor that has done many F1 circuits. All new extended curbing will be built to exacting FIA standards, and the 12-hour enduro will be the first event on the new pavement.
Before the 25 Hours of Thunderhill became the longest closed-course endurance race in North America in 2003, it was the 12 Hours of Thunderhill. Before that, it was six hours, and before that it was three hours. The 25 Hour now takes place at Ozarks International Raceway this June, so the West Coast was primed for a good long enduro this September at Thunderhill Raceway.
“I have always loved the challenge of endurance racing, and I know a lot of racers in the western part of the country do, too,” said NASA NorCal Regional Director Jerry Kunzman. “By adding a 12-hour enduro to our event calendar, we can expose veterans and new racers to the joy of endurance racing, with the simplified structure of TREC rules. Twelve hours seemed like just the right length, and I think it’s going to be a big hit.”
Arrive-and-drive teams are encouraged to contact [email protected] for multicar discounts. Reserve your spot on grid for the 12 Hours of Thunderhill this September.
