Luptow was born at Markesan, Wisconsin to Frank and Ida Lueptow in 1914 with Dutch heritage.

[1] After his discharge from the military, he moved back to Detroit and worked for a tank manufacturer.

[1] Luptow won 1948 IMCA races at Lebanon, Ohio, Eldon, Iowa, Danville, Illinois, Nashville, Tennessee, Plant Field (Tampa, Florida), Speedway Park (Tampa), and Birmingham, Alabama.

[1] Luptow started the 1949 season by replacing his Hal engine with an Offenhauser and his car began to be known as the "Black Panther.

[1] He also competed in a NASCAR Grand National (now Cup Series) stock car race, finishing 18th at the season-opening Daytona Beach Road Course.

[1] Luptow switched to stock cars at the behest of his wife, who wanted him to quit entirely because of the danger of open-wheel cockpits.

[2] In the stock car, he won twice in August at the Milwaukee Mile and the Terre Haute Action Track.