Phil Cavali/ESPN(CHARLOTTE, N.C.) -- 2004 NASCAR champion Kurt Busch and Penske Racing have decided to part ways.  At the 2011 season finale at Homestead-Miami, Busch was seen making an obscene gesture and directed a profanity-laced tirade at a reporter.  He was reprimanded by both NASCAR and Penske.

"I am grateful to Penske Racing for six very productive years," Busch said in statement. "Together we won a lot of races, 16 in all. It's time for a fresh start.  Leaving a great organization and a lucrative contract is not easy, but it's an important step for me and allows me to take a deep breath to work on things that can make me a better driver and a better person."

In a statement, Penske team owner Roger Penske said the split was "best for all parties, including our team and sponsors."

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