Kyle Busch, driving the Joe Gibbs Racing No. 18 Toyota, topped the speed chart in Nationwide Series practice Friday morning at Darlington Raceway. Busch's lap at 173.003 mph was fastest of the 43 drivers who participated in the nearly three-hour session.

Clint Boywer clocked in second fastest with a lap of 171.734 mph followed by Carl Edwards, Kasey Kahne and Reed Sorenson.

Qualifying for Friday night's Royal Purple 200 is set to begin at 3:35 pm this afternoon.

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