Three more race tracks have announced safety modifications that were determined necessary following Kyle Busch's serious accident at Daytona.
Busch broke his right leg and left foot when he crashed into a concrete wall at Daytona in February. It has spurred industry-wide inspections to see if the walls at most tracks have enough protection to prevent an injury.
Texas Motor Speedway has added 250 feet of tire barriers in preparation for NASCAR's visit next week.
Bristol Motor Speedway will add 600 feet of SAFER barrier to the front and backstretch outside walls before the race on April 19.
Michigan International Speedway will add the steel-and-foam energy reducing barriers to pit-in and pit-out walls, and tire packs will be installed at the angled wall inside Turn 1 before NASCAR's visit in June.