Event #5334: Sep 18th - 19th, 2026
12 Hours of Thunderhill
Event Information
Outlook DesktopDate: Sep 18th - 19th, 2026
Track Name: Thunderhill Raceway Park
Event Type(s): Endurance Racing
THE 12 HOURS OF THUNDERHILL IS BACK!
Going back to its roots, NASA NorCal presents the 12 Hours of Thunderhill — twelve straight hours of endurance racing at Thunderhill Raceway Park.
From the green flag at 7:30 AM to the checkered flag at 7:30 PM, you and your team will have twelve hours to prove what you've got.
Strategy. Traffic. Driver changes. Fuel stops. Mechanical challenges. And a whole lot of racing.
Whether you're putting together your first endurance team or you're an experienced racer looking for maximum track time, the NASA NorCal 12 Hours of Thunderhill is designed to deliver an unforgettable weekend of racing without the complexity and expense of many traditional endurance events.
RACE WEEKEND
Friday, September 18
Practice and qualifying from 4pm-5pm
Saturday, September 19
12 Hours of Racing — 7:30 AM to 7:30 PM
Teams will receive assigned paddock and pit spaces, giving you plenty of time to get your team, equipment, and pit area ready before the race.
ONE TEAM. ONE ENTRY FEE. TWELVE HOURS OF RACING.
$2,195 covers your entire team. Bring as many drivers and crew members as you need — there is no additional per-driver or per-crew entry fee.
The Team Racing Endurance Challenge (TREC) is designed to make endurance racing fun, competitive, safe, and accessible. Straightforward licensing requirements, open tire rules, timed fuel stops, and time-based classes eliminate many of the barriers that make endurance racing expensive or intimidating.
It's a great way to get your first taste of endurance racing — and a great excuse for experienced racers to spend twelve hours doing what they came to the track to do: race.
WHY TREC?
- Five time-bracketed classes create close, competitive racing without complicated vehicle classifications or post-race impound.
- No NASA competition license required.
- Daylight-only racing means no expensive endurance lighting setup is required.
- Strict NO CONTACT rules help keep the racing clean and the cars on track.
- Five-minute timed fuel stops in all classes except Unlimited help control costs and reduce fueling advantages.
- Standard fueling jugs are used in all classes except Unlimited.
- Open tire rules let you choose the tire that works best for your car and budget.
- Unlimited drivers and crew are included with your $2,195 team entry.
- Live-stream race coverage lets friends, family, and fans follow the action.
- Prizes and awards will recognize not only the top finishers, but special achievements including Oldest Car, Hard Luck, Best Effort, and more.
CLASSES
Pick your class based on your team's declared minimum lap time:
TREC U — Unlimited
TREC 3 — 1:54
TREC 4 — 2:00
TREC 5 — 2:05
TREC 6 — 2:10
The time-bracket format means you don't need the fastest or most expensive car to be competitive. Pick your target, build your strategy, and race your class.
TIRES
Tires are open — including slicks.
Run the tire that works for your car, your team, and your budget.
A maximum of two tires may be changed during a pit stop, except in the Unlimited class.
WANT MORE TRACK TIME BEFORE THE WEEKEND?
Thunderhill Raceway Park is offering a separate open test opportunity for teams wishing to test prior to the NASA race weekend.
This test day is organized and operated by Thunderhill Raceway Park and is not part of the NASA NorCal event. The test operates under Thunderhill Raceway Park's insurance and event requirements.
Test-day registration and information are available directly through Thunderhill Raceway Park:
https://www.motorsportreg.com/events/3-mile-open-test-thunderhill-raceway-park-409321
Full weekend schedule:
TREC RULES
Complete rules:
https://docs.google.com/document/d/1NLHSkfHhPd1vPLBoGjKLR_RjXN3XVDf0CnqkgsJSYLY/edit?usp=sharing
Pit lane and paddock parking assignments:
MAKING THE GRID — FOLLOW THE RACE BEYOND THE TRACK
The Making the Grid TV show will be at Thunderhill capturing the stories behind the race.
Airing on the new automotive channel PowerTube TV, available through streaming platforms including Roku, Amazon Fire TV, Apple TV, Android TV, and others, Making the Grid takes viewers behind the scenes of motorsports.
During the 12 Hours of Thunderhill, the production will follow several teams throughout the event — from preparation and strategy to driver changes, pit stops, setbacks, repairs, and ultimately the fight to reach the checkered flag.
It's not just about who wins.
It's about what it takes to survive twelve hours of Thunderhill.
TWELVE HOURS. ONE TEAM. ONE CHECKERED FLAG.
You've got the car.
You've got the drivers.
Now put the team together and come race with us.
NASA NorCal 12 Hours of Thunderhill
Saturday, September 19
7:30 AM – 7:30 PM
$2,195 per team — unlimited drivers and crew.
See you at Thunderhill.
Registration is closed for this event!
