Coming into the 2021 25 Hours of Thunderhill Presented by Hawk Performance, Team Entropy Racing EVSR Electric Racing Team estimated it would have to swap the two 350-pound batteries every nine to 11 laps, but it ended up with an efficient 14 laps per battery change. Thunderhill Raceway set the team up with a charging station near the entrance to the track, allowing the team to shuttle the batteries back and forth using a heavy-duty cart.
A few hours into the race on Saturday, the motor was running hot because the ambient air temperature was above 64 degrees Fahrenheit. The crew used distilled water to cool the motor and the 11-hour fog delay cooled it even further.
“This was not our most challenging race by any stretch. The buildup to it was the most difficult thing I’ve ever done in my career and probably the most rewarding,” Charles Greenhaus, Lead Engineer said. “The pace for the race was significantly slower because we were managing temperature. But with this same car, with some modification, we believe we could run a sub 2:10 pace for an entire 25 hour race.”
The team finished 29th overall out of 36 cars. For 2022, the team is hoping to finish higher and has implemented solutions to the overheating problems.
“We had some motor cooling issues last year which required some creative, on-the-spot problem solving. When we got back to the shop post event, we got to work on a permanent fix,” Greenhaus added. “By improving the motor cooling injection system to our rear motor and increasing airflow we are confident we will be within normal temperature limits throughout the race and have had the opportunity to prove this during rigorous testing throughout the 2022 season. We look forward to running a better race this year.”