Twenty-Five Hours of Thunderhill: Something For Everyone

Twenty-Five Hours of Thunderhill: Something For Everyone

by | Dec 6, 2016

BMW once again take top places in one of the world’s longest endurance races

Most of you know about the longest closed course race in America that is held every year in our own backyard. But for those of you who haven’t heard of the 25 Hours of Thunderhill, it is quite simply one of the most grueling endurance races in the world. Run by NASA (National Auto Sport Association), this was the 13th running of the event on the Thunderhill Racetrack located in the Northern California town of Willows. This year, the green flag dropped at 11am on Saturday, December 5th and the checkered came out at 12pm on Sunday the 6th.

One of the many racetrack jewels that we’re lucky to have here in Northern California, the 25 hour race is run on the old or “short” course. The new west-side track gives the potential of a 5 mile lap, but would simply be too difficult to cover adequately for an endurance race of this length. The East Course is 15 turns and 3 miles in length. It’s a good mix of straights at full throttle, technical elevation changes and tight, off-camber corners.

Of course, one of the added difficulties of this particular race is the large difference in lap times between the all the classes. This year the fastest car ran a sub 1:40 and the slowest was over 2:10! As many of you know, the remote location can bring crazy weather. We’ve had all sorts over the years and this year would be no different. Rain had been coming in on and off all week and qualifying saw mixed conditions with everyone trying to keep out of trouble. After all, for a race of this length, it’s definitely not where you start, but where you end up!

As I drove out to the race track on race day, it was cold, but not the sub-freezing we’ve seen in past years. All forecasts clearly showed that we should expect rain to come in throughout the night and if we were lucky, clear up after dawn. The race started under clear and fast conditions. No major accidents though the first ½ an hour or so and the race settled into a good tempo. After a few hours of beautiful weather, the clouds started coming in thick and fast and by 4pm, it was so dark it felt like we were in the middle of the night. There would be no spectacular sunset during this race. Just after 9pm, earlier than expected, the rain began. It would intensify at times and then slack off to a light drizzle but never completely left.

The rain never stopped, in fact the race almost finished under full course yellow.

Warmer than normal temperatures were welcomed by the teams in the early hours of the morning, however, the rain continued to fall. Alas, there was no dawn, just a gradual lightening of the gloom that surrounded the track. The rain never stopped. In fact, the race almost finished under full course yellow. Fortunately the track went green with about 15 minutes left, setting up exciting last laps for some of the competitors.

When the 25th hour finally struck, the checkered flag was flown for the Flying Lizard Motorsports Audi R8LMS to claim the overall and ES class victory. The car and team were a model of consistency throughout the race and they finished a dominant 690 laps, 35 laps clear of the field. Fast the entire race, the Audi was piloted by some notable professional drivers including Johannes van Overbeek, Darren Law and Guy Cosmo.

If you read my report in the eBombe last year, I closely followed the local Stammer Racing/Bavarian Performance team out of Marin County with their E46 M3. Last year they finished a very respectable 2nd in class and third overall. (The highest a BMW has finished the race in many years.) Once again, they had another strong result as they finished 2015 4th overall and 4th in class in an extraordinarily competitive ES class. In the end as the full course yellow cleared, they had the Gryphon Racing Praga prototype breathing down their neck, on the same lap and easily turning 15 second quicker times. With just two laps left, driver Derek Welch had his rear view mirror filled with the red prototype sitting on his rear bumper. For those two laps, he made that E46 exceedingly wide and finished ahead of the Praga by only .697 of a second! 25 hours and less than a second separated those two teams.

Crazy stuff! In the past ten plus years I’ve never had a 25 hour finish even on the same lap, much less within a second.

Derek gave us his view of those last laps. “On the 2nd to last lap the Gryphon made up the gap and was within a few car lengths. I had to really focus and work traffic whilst taking risks. This was it. Last lap, hero or zero… Turn ten I got slightly overly ambitious with the throttle, car snapped sideways, I gathered it up and sneaked passed a Miata just before the back straight. With a decent run and two corners remaining I managed to hang on with him on my tail. Crazy stuff! In the past ten plus years I’ve never had a 25 hour finish even on the same lap, much less within a second.”

In another example of the dangers of endurance racing, Stammer team owner and driver Jeff Stammer would succumb to a race-ending injury… a compound fracture in his leg. This wasn’t a racing accident though, it happened in the pits! The One Motorsports Team with their ultra-fast Radical were pitting right next to the Stammer Team. Around 2am, there was a miscommunication amongst the team and the driver drove off with the air jack hose still attached. The metal fitting ripped off and the high pressure hose began to whip around the adjoining pits. In the melee, diving out of the way, Jeff broke his leg. The One team were DQ’d, but unfortunately for Jeff, it meant the end of the race and a visit to the hospital followed, no doubt, by months of recovery. Get better soon Jeff!

In the E0 class, it was a podium sweep by BMWs. The El Diablo Motorsports/BimmerWorld of Sacramento 325 took the top step with 617 laps, only 9 laps behind the Stammer & Gryphon dice and 10 laps in front of the EDGE Motorworks E46 M3. Finishing a futher 4 laps behind for 3rd place was the RoadShagger Racing M3. Interestingly, one of the partners in the El Diablo Motorsports team pulled out this year and they nearly didn’t field an entry this year.

Lance Boicelli, Owner/Driver of El Diablo Motorsports talks about what happened: “…with less than three months to the event, I set my sights on the Bimmerworld WCTC E46 race car I had picked up over a year before, sitting in my barn shop.” Enter his friend and this year’s race team partner James Clay, founder of Bimmerworld. “James’ and Bimmerworlds’ decades of experience and technical partnerships created a specs package to update the potent 15 year old race car platform and off we went running. I’ll admit, there were times were I thought I wasn’t going to pull it off, in fact the Sunday before the race the new brake lines were giving me so much grief I was ready to throw in the towel.”

The results spoke for themselves, however, as he gave his thoughts post race: “Everyone did an awesome job keeping the car on the track, clear of incidents and penalties, allowing us to finish 10+ laps up on second place car. In a word, spectacular. Having won this race three times out of the last four years I can honestly say that the friendship and camaraderie experience by this event is equally cherished as that winning feeling.”

A class level down in E1 saw a dominant Grip Racing Team take both the 1st and 2nd place trophies. In fact this “BMW” class saw 6 of the top 7 spots taken by either a 330 or an M3. Grip Racing is a Pacific Northwest based racing team, however, they fielded their second car entirely with California drivers. That car, the #0 Tic Tac themed car won the class and was driven by Mark Drennan, Mason Filippi, Rylan Hazelton, Addison Lee and Brian Ghidinelli.

Brian told me what he thought about this race. “It was cold, dark and nasty! Teams have to be at their very best just to finish this thing and Grip Racing brought expertly-prepared cars and performed nearly 50 perfect pit stops keeping us out on track. This is my fifth attempt to conquer the 25 so watching the cars cross the finish line together in 1st and 2nd was very special.”

BMWs may not be the fastest cars in this amazing race and the professional teams keep pouring in with bigger budgets and faster cars, more every year. But our teams are certainly showing to have the best combination of preparation, speed and reliability. When it comes to the 25 Hours of Thunderhill, we still have the ultimate driving machines!

This was Ingo Schmoldt’s seventh year covering this race. He is the owner of Ingo’s Images based in the San Francisco Bay Area. He specializes in photographing automobiles for owners out on location or on track. His work can be found on Facebook ( or Instagram (

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