NASCAR will require additional air ducting this weekend at Michigan International Speedway, to combat high temperatures experienced three weeks ago at Indianapolis Motor Speedway.
Sunday’s race will be the second to utilize a new, high-drag aerodynamic package, which many blamed for cockpit temperatures in excess of 140 degrees at the Brickyard. Longer rear-fender extensions acted to reduce airflow beneath the cars, trapping additional heat and causing a number of drivers to suffer from heat exhaustion.
Teams received a written bulletin from the sanctioning body today that increases the number of right-side window air intake ducts from one to three, in an effort to lower in-car temperatures. The additional air ducts were optional at IMS, but most teams elected not to run them, in order to achieve maximum downforce. Today’s bullet makes those ducts mandatory.
Former Sprint Cup Series champion Brad Keselowski said earlier this week that he expected Sunday’s race to be “the toughest race of the year physically.”
The National Weather Service projects a high temperature Sunday of 89 degrees.