The idea of Stewart, then a two-time Cup champion driving for Joe Gibbs Racing, sharing ownership in a Cup team with billionaire machine-tool businessman Haas, seemed to come out of nowhere in 2008.

Gene Haas wanted to enter F1 to promote his machine-tools business, and Steiner set up the team with a plan to buy as many parts as possible from Ferrari. Haas do the minimum required by the rules ...