In 1956, DeLorean accepted a salary offer of US$16,000 () with a bonus program, choosing to work at GM's Pontiac division as an assistant to chief engineer Pete Estes and general manager Semon "Bunkie" Knudsen. Knudsen was the son of the former president of GM, William Knudsen, who was called away from his post to head the war mobilization production effort at the request of President Roosevelt. Knudsen was also an MIT engineering graduate, and at 42 he was the youngest man to head a division of GM. DeLorean and Knudsen quickly became close friends, and DeLorean eventually cited Knudsen as a major influence and mentor. DeLorean's years of engineering at Pontiac were successful, producing dozens of patented innovations for the company, and in 1961 he was promoted to the position of division chief engineer.