The debut of NASCAR’s high-drag rules package plus stifling heat made for some exhausted drivers after the Xfinity and Sprint Cup race at Indianapolis Motor Speedway last month.
Team Penske’s Brad Keselowski said the return of high drag this weekend at Michigan International Speedway could be much more taxing, resulting in what will be “the toughest race probably of the year physically” for drivers.
“The heat’s going to be even worse this weekend,” he said during a Tuesday conference call with the news media. “There is a large amount of concern across both the teams and the driver for this rules package coming up to Michigan. Even though the track is wider and bigger, the significance of the draft is going to be even more important, so you’re going to have to stay in line as much as possible. As you stay in line, the car gets less and less air because that’s essentially how the draft works.”
The new package employs a much taller 9-inch spoiler and a rear bumper extension, which contributes to sealing off the cockpit from airflow.
Keselowski said there also is concern about durability because of the high speeds at Michigan. The 2-mile oval is the fastest in NASCAR with pole speeds surpassing 200 mph since a repaving three years ago.
“(That) means the parts, specifically the drivetrain, are going to be even hotter,” Keselowski said. “The team is very, very concerned about the drivetrain, everything from the engine all the way back to the axles, because they’re really not made for these temperatures.
“We kind of build our cars at 110 percent rule, which is if 100 percent is what you expect a car under normal loads to carry. You build in another 10 percent safety margin. Well, that 100 percent was based around the rules package that we began the year around, and this particular iteration of that rules package has more than eaten up that 10 percent margin that we theoretically work around with the cars.
“So I would not be surprised to see a lot of car failures this weekend specific to heat relation as it pertains to the aero package and its kind of cause and effects. And inside the car I would not be surprised to see a lot of hot and worn out drivers after the race. We all know we’re in for a handful of a race.”
Temperatures are forecast to be in the mid-80s for Sunday’s Pure Michigan 400.