NASCAR sent a rules update to Cup Series teams with changes to the cars to take effect this weekend at Kansas Speedway, in hopes of stopping a rash of fires affecting Next Gen cars.

Kevin Harvick’s car caught fire at Darlington Raceway because of rubber buildup, prompting more lashing out at NASCAR by Harvick as he continues to express his displeasure with the Next Gen car. NASCAR had already mandated an update to the exhaust shroud going into Richmond Raceway last month after Chris Buescher and Joey Logano’s cars caught on fire at Indianapolis, and the sanctioning body has now made the following additional directives:

• A lateral seal/dam must be installed between the back of the front clip weight box and the top of the splitter panel. This seal must extend laterally to the width of the engine panel. The seal/dam is intended to reduce the migration of tire debris from the splitter area.

• The lower front section of the right-side back stop panel has been trimmed, while the section that is removed must be replaced by a 14 gauge stainless steel panel. The steel panel must be mounted inboard of the polymer panel.

• Using any join adjustment available in the exhaust assembly, it is recommended that the clearance between the exhaust and the floor of the rocker box is maximized.