Turn 3 Motorsport Wins NASA’s 25 Hours of Thunderhill In A Radical

Annually the USAF 25 Hours of Thunderhill presented by Hawk Performance attracts teams from all over the world who want to take on the grueling endurance race, an event that is one-hour longer than the famed 24 Hours of Le Mans. This year on December 7-8, 2019, in Willows, California, about an hour north of the state capital, you could hear drivers speaking both French and Japanese. It didn’t matter what dialect the drivers were using during the National Auto Sport Association (NASA) 25 Hours of Thunderhill, the universal language was speed.

At TURNology, we get excited about this race because it is an event where the pros don’t have any races occurring in December, so they come out to play in the ESR class. While at the same time, average joes in a Spec Miata also get to battle it out for 25 Hours in the E3S class. With eight different classes competing at the same time, through the night, the action on-track is constant.

The California Highway Patrol in a Dodge Charger paced the first lap of the 2019 25 Hours of Thunderhill. In the background on the grid, you can see teams doing their best to keep their drivers dry in open-cockpit cars before the start of the rainy race.

We have been talking about the race for weeks here at TURNology, covering the contingency money you can win from Toyo Tires ($10,000 for the GT Challenge class winner), and reviewing the documentary film about the 25 Hours of Thunderhill titled Double Down. Finally, after all of the hype, it was Saturday at 11:00 a.m. The race was about to start to run around the clock (plus one-hour more) until noon on Sunday when the overall winner and class winners would be crowned.

This race is scheduled each year during the first weekend in December, which makes for some interesting racing weather in Northern California. Some extremely heavy rain and wind hit Thunderhill right as the race began. Teams needed to take it easy for the first few laps, but adrenaline and egos often take over during moments like the start of a big race. When the green flag dropped, the rooster tails went up and it was on for 2019 — with 25 hours of hard racing to go.

Green Flag

The first laps of the 2019 NASA 25 Hours of Thunderhill were rain-drenched. The rooster tails sailing off the back of the prototype cars made visibility for cars behind them extremely difficult.

With the low-profile design of the fast prototype cars in the ESR class, along with the wet weather, all you would see going down the straight is a blur and a rooster tail of water. Here is pro driver Ryan Eversley flying the JFC Racing 1, 2012 Lola B12/80 in the ESR class.

We spoke with Troy Lindstrom, driver of the bright orange number 56 BMW running in the E2 class for team Sampson Racing Communications, who said visibility was extremely bad during the start of the race. “Yes, the track was wet, but the car was working well with the tires, I just couldn’t see anything. It was just a blur, and then I would catch a glimpse of the edge of the track and think, okay, I know where I am. It was crazy.”

During the first few laps, it was obvious which cars would have an advantage in the bad weather. Team Honda Racing THRW 2 in their 2018 Honda Civic Type R was ripping through the field, using the front-wheel drive to its advantage in the wet. The team led the E0 class during the early hours of the race.

The 2018 Honda Civic Type R of Honda Racing moved through the field during the bad weather and then took the lead in E0 during the early parts of the long race.

Pit Stop Strategy

During the race, it would rain like crazy, then it would dry out and things would speed up. Then the rain would come back. This ever-changing weather made for a lot of debate for the teams about what tires to put on a car (slicks, intermediates, or rains). This decision was a tough one to make, because NASA rules for changing tires in the E3, E3S, E2, E1, and E0 class cars mandate you can only change one tire during a stop on pit road.

So, if you wanted to do a four-tire change that would mean a trip into the paddock. But it gets more complicated there. In the paddock, you cannot fuel the car. That has to be done in the hot pits. Understanding the rules, pit lane position, and strategy play a huge role in the long 25-hour battle. In order to win, you have to get all of it right.

The crew for the Sampson Racing Communications team, running a 1993 BMW 325is in the E2 class, are huddled in their transporter away from the rain endlessly debating which tires to use. As soon as they would come up with a consensus, the weather would change, and they would have the discussion all over again — for 25 hours.

This race is extremely long and hard on equipment. To give you an idea of how much stress is put on a car, most teams will run an entire regional season of road racing without putting 25 hours of track time on a car (that is including practice, warm-up, qualifying, and testing).

That full racing season comes with hours and hours in the shop between weekend races prepping the car and servicing it. At the 25 Hour, there is no time for lengthy service. There is only time for gas, driver swaps, a tire change, and maybe a quart of oil. Anything longer than that and your team will be behind on laps.

Quick pit stops are the name of the game at the 25 Hours of Thunderhill. Every person has a job and they need to execute it quickly and efficiently.

The Streak

The rain came and went, and as the race headed toward darkness Saturday night, eyes were on Flying Lizard Motorsports. It was running a 2018 Audi R8 LMS GT4, an all-wheel-drive capable machine, which won this race before. In fact, the Toyo Tires-sponsored Flying Lizard Motorsports won the event overall four-years straight: 2015, 2016, 2017, and 2018. Would they be able to keep the streak going? Could they win it five years in a row? Only the racing Gods could know.

Four-time-consecutive overall winners, Flying Lizard Motorsports, came out to defend its title and the winning streak racing a 2018 Audi R8 LMS GT4 for the 2019 25 Hour.

Factory Teams

Not only was Honda Racing in the event as a factory supporter but Toyota was there as well with its Toyota Arizona Proving Grounds Team, known as TAPG Motorsports, driving a Toyota FR-S, or “86” as they like to call it. Pro driver Randy Pobst was behind the wheel of the Toyota.

As the first ten hours of the event clicked off, things were looking good with Honda leading the E0 class, and Toyota leading in E2. Flying Lizard Motorsports was running well too. The pro teams were looking solid, as they should be…

Then the day turned into night, and everything changed.

The Toyota 86, run by TAPG Motorsports, had Randy Pobst behind the wheel in the E2 class. The team lead a large portion of the race in the E2 class… and then they didn’t.


The nighttime changes things at the 25 Hours of Thunderhill. It happens like this every year. The first casualty was Flying Lizard Motorsports, shunted off track and out for the race. Their streak was over. Then, it was mechanical issues for Honda Racing in the CTR, losing its prominent lead. Toyota held strong through the night, leading E2. It wasn’t until the sun rose that problems arose for TAPG Motorsports (with unfortunate off-track excursions in the mud).

Things go down at night at The 25. If you ask the drivers what happened when they bring the car into the paddock with fresh damage, they will rarely admit anything: “I dunno, it’s The 25 at night.”

Sun Rises On The Winners

When the checkered flag fell 25-hours after the race began, there was electricity in the air. Teams had done it! They had survived the 25. Sure, everybody wants to win, but just finishing this race is an enormous accomplishment. Earning a podium finish is the icing on the cake.

Here are the winners of each class (each class is listed in order of the most laps completed). The podium finishers are listed under the photos of the class winners:


GT Challenge







Overall Winner

All the teams who won their classes will have this victory to remember for the rest of their lives, but only one car can be the overall winner. For 2019, that team was Turn 3 Motorsport driving a Radical. Drivers Peter Dempsey, Eric Wagner, Antoine Comeau, and Neil Alberico completed 672 laps (which equals over 2,000 miles) — in the rain — in an open cockpit racecar. Insane!

Your 2019 NASA 25 Hours of Thunderhill overall winners, Team Turn 3 Motorsport!

The mud and grime show the hard work this Radical endured to travel 2,016 miles to become the 2019 25-Hour Champion.

Congratulations to all of the teams for a safe race. For those of you who want to run in 2020, start preparing now because there are only 364 days left to get ready, and this race takes a lot. For more information and results, visit USAF 25 Hours of Thunderhill presented by Hawk Performance.

(Photos courtesy of NASA by photographers: Herb Lopez, Rob Krider, Brett Becker, and Doug Berger.)

Also, check out this cool video from Toyo Tires to get a feel of what this year’s event was all about!

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About the author

Rob Krider

Rob Krider will race absolutely anything. He is a multi-national champion racing driver and is also the author of the novel, Cadet Blues.
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