The Champ Car World Series, which has run a doubleheader with the NASCAR Craftsman Truck Series the past two seasons, will not return to Las Vegas Motor Speedway in 2006. The announcement was made Tuesday by LVMS officials. "The September race weekend started out as a stand-alone truck race, and it will continue to thrive as a stand-alone event," said LVMS general manager Chris Powell. "We have enjoyed having the Champ Cars here the past couple of years in what has become a very unique motorsports doubleheader. We look forward to continuing our relationship with the NASCAR Craftsman Truck Series to make this event even bigger in the coming years." The Las Vegas 350 NASCAR Craftsman Truck Series event is scheduled for Saturday, Sept. 23, 2006. Champ Car World Series champion Sebastian Bourdais won both Champ Car events held at LVMS in 2004 and 2005.