This weekend the stars of the NASCAR Sprint Cup Series are in the Irish Hills of Michigan for the LifeLock 400. Friday afternoon the Cup cars hit the track for a ninety-minute practice session in preparation for the weekend's events.

When the black-and-red flag flew to end the session, Hendrick Motorsports' Jimmie Johnson was atop the leaderboard with a lap of 38.132 seconds at a speed of 188.818 mph. Looking for his first victory at the 2-mile D-shaped oval, Johnson was able to post the fastest lap of the session.

Red Bull Racing's Brian Vickers ran the second-fastest lap of the weekend's opening session. The driver of the No. 83 Red Bull Toyota had a quick-lap of 38.174 seconds at a speed of 188.610 mph. Atlanta winner Kurt Busch was third-fastest with a lap of 38.192 seconds at 188.521, followed by Earnhardt Ganassi Racing's Juan Pablo Montoya and Richard Childress Racing's Clint Bowyer.

The biggest news of the session came when smoke began to come out of the No. 24 Chevrolet driven by Jeff Gordon. The four-time champion shut the motor off as he drove past the start/finish line after feeling a miss in the engine. The team was forced to replace the engine, which will put them at the rear of the field come Sunday.

FULL PRACTICE RESULTS

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