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Safety measure: NASCAR updates Talladega rules package

TALLADEGA, Ala. — NASCAR competition officials issued a Friday afternoon rules update to further reduce horsepower after observing blistering speeds and a rollover crash in Monster Energy Series practice.

Officials reduced the size of the engine restrictor plates from 7/8 of an inch to 55/64th of an inch in an effort to slow the cars ahead of Sunday’s GEICO 500 (2 p.m. ET, FOX, MRN, SiriusXM NASCAR Radio) at the 2.66-mile track. All practice was completed Friday, so teams will make their first laps with the new rules in Saturday’s Busch Pole Qualifying (1:05 p.m. ET, FOX, MRN, SiriusXM).

A NASCAR spokesperson said the change was “absolutely a safety issue” and that the series was positioned to react when cars lift off the racing surface.

Two Friday events prompted the change. The most dramatic episode was Jamie McMurray’s tumbling crash on the backstretch early in final practice. McMurray’s No. 1 Chevrolet lifted in a sideways slide before being sent up and over by contact from Ryan Newman’s No. 31 Chevy. McMurray emerged unhurt.

Practice speeds also reached high levels in both sessions. Ty Dillon topped early practice at 202.959 mph, and McMurray’s lap of 203.975 mph was fastest in the final session.