There were problems. The new 1.6-mile road course around the Pepsi Center was by turns too rough and too slick. The pedestrian bridges were overcrowded. A stand of young trees along Auraria Parkway blocked the view of high-rollers holding $800 tickets. But the return of Indy car racing to the streets of the Mile High City -- the first Shell Grand Prix of Denver -- proved an exciting diversion for 40,000 motorheads who crowded into the sun-kissed venue on Labor Day. The race's sanctioning body, Championship Auto Racing Teams (CART), faces defections by some top drivers and engine-makers, but the show will go on again this summer. Meanwhile, the best T-shirt spotted at the inaugural race on September 1: "Too Dumb for Opera. Too Smart for NASCAR."