NASCAR requires extra airflow at Michigan to battle heat
With concerns the return of a high-drag rules package again will cause excessive cockpit temperatures, NASCAR is mandating extra air ducts this weekend at Michigan International Speedway.
In a rules bulletin being distributed Wednesday to teams, a dual outlet duct is required on the right-side window of the car for Michigan. That will increase the right-side openings to three, helping ventilate the cockpit to keep drivers cooler.
The high-drag configuration, which is used in the Xfinity and Sprint Cup series, employs a rear-bumper extension that contributes to reducing airflow underneath the car, trapping more heat beneath it when the side skirts are sealed to the track at speed. After the debut of high drag in the Xfinity race at Indianapolis Motor Speedway, some drivers were battling heat exhaustion.
Speeds at Michigan will be much higher than Indy, meaning engine heat also figures to be considerably hotter. In a Tuesday conference call with the news media, Brad Keselowski said he expected Sunday’s Pure Michigan 400 to be the “toughest race of the year physically.”
Teams have the option of running extra openings in the windows to direct air to cool the driver, but there’s a negative tradeoff in less downforce that will affect performance. NASCAR’s new rule essentially removes the burden from teams having to choose between speed and a potential safety enhancement.