UMP Nationals Click each thumbnail for photos from a soggy Eldora Speedway, where rain has forced the postponement of the Friday portion of the UMP DIRTcar National Championships. The entire event will be run on Saturday, October 6th. Click each thumbnail for photos from a soggy Eldora Speedway, where rain has forced the postponement of the Friday portion of the UMP DIRTcar National Championships. The entire event will be run on Saturday, October 6th.