Since 1997 Ludvigsen has been drawing on the photographic resources of the Ludvigsen Library to write and illustrate books on the great racing drivers. His first title in this series was Stirling Moss - Racing with the Maestro. He followed this with Jackie Stewart - Triple-Crowned King of Speed and Juan Manuel Fangio - Motor Racing’s Grand Master. Fourth in this series for Haynes Publishing was Dan Gurney - The Ultimate Racer and fifth was Alberto Ascari - Ferrari’s First Double Champion. Next came Bruce McLaren - Life and Legacy of Excellence and Emerson Fittipaldi - Heart of a Racer.
Also in the field of motor sports Karl Ludvigsen has written about road racing in America, the cars of the Can-Am series, the AAR Eagle racing cars, the GT40 Fords and Prime Movers, the story of Britain’s Ilmor Engineering. His introduction to At Speed, a book of Jesse Alexander’s racing photography, won the Ken W. Purdy Award for Excellence in Automotive Journalism. Other motors-sports titles include Classic Grand Prix Cars, a history of the front-engined G.P. racer, and Classic Racing Engines, Karl’s personal selection of 50 notable power units.