In the spring of 1963, Ford reportedly received word through a European intermediary that Enzo Ferrari was interested in selling to Ford Motor Company. Ford reportedly spent several million dollars in an audit of Ferrari factory assets and in legal negotiations, only to have Ferrari unilaterally cut off talks at a late stage due to disputes about the ability to direct open wheel racing. Ferrari, who wanted to remain the sole operator of his company's motor sports division, was angered when he was told that he would not be allowed to race at the Indianapolis 500 if the deal went through since Ford fielded Indy cars using the company's engine, and didn't want competition from Ferrari. Enzo cut the deal off out of spite and Henry Ford II, enraged, directed his racing division to find a company that could build a Ferrari-beater on the world endurance-racing circuit.
Source: Wikipedia (original)