NASCAR will use restrictor plates for the Xfinity Series event in July at the Indianapolis Motor Speedway. The Sanctioning Body released the basic technical rule changes for the 250-mile event that includes the continued use of a tapered spacer, a 7/8ths-inch restrictor plate and air ducts to move air out of the front wheel wells.
The hope, after it was used in an October 2016 test, was that the high speed air flowing out of a leading car will create a larger hole for the trailing car. It’s believed that the trailing car will pick up a 25 percent increase in horsepower due to the pocket.
NASCAR is essentially looking to create a slipstream effect.
The race has been one of the most procedural in the recent history of NASCAR since the event was moved to IMS from the Lucas Oil Raceway short track in nearby Brownsburg, Indiana back in 2012.
The hope is that the rule changes keep cars closer together for the second-tier national touring division. These changes are for the Xfinity Series event only but is rumored to be adapted for the Cup Series and other tracks should it prove successful in July.
NASCAR also stated the package will include a taller spoiler and wider splitter. IMS track President J. Douglas Boles made the following statement about the new equipment package.
“We’re encouraged and supportive of this change by NASCAR and appreciate the collaborative effort to enhance the overall fan experience during this event,” Boles said. “The lineup for the entire weekend is exciting, starting with the Fan Fest on Friday, a full day of Monster Energy NASCAR Cup Series and NASCAR XFINITY Series action on Saturday and the 24th annual Brickyard 400 on Sunday.”