INDYCAR announced today it has implemented the use of closure panels to the rear wheel guards of both Honda and Chevrolet superspeedway aero kits beginning this weekend at Texas Motor Speedway. The panels were developed by Honda and Chevrolet, respectively, and will also be utilized at Pocono Raceway and Auto Club Speedway during the 2015 Verizon IndyCar Series season.
“This has been a collaborative effort with both manufacturers and they have been working on these since the Indianapolis 500 qualifications,” said Will Phillips, INDYCAR Vice President of Technology. “These closure panels serve as a blocker so air cannot flow through the rear wheel guards. This will ultimately raise the point at which cars would experience lift when traveling backwards.”
INDYCAR also confirmed that the rear wing angle for all entries this weekend must be set between (-6) and (-10.5) degrees, which will still result in an increase in overall downforce compared to the 2014 event at TMS.
SOURCE: INDYCAR