Five-time champion of the International Motor Sports Association's GT Championship Series.
He started racing in the amateur leagues in the early 1970s, and then turned professional in '74.
He drove in 19 NASCAR races, finishing 4 times in the top 10.
His father Bob Holbert was an auto dealer near Warrington, Pennsylvania.
He and Bill Whittington both competed in the 24 Hours of Le Mans series.