Tuhia he tomokanga mō tēnei wāhanga - Kāore i rahi te rāngai pūkaha o te Mustang ki te whakauru i te pūkaha Boss 429 nui, nō reira ka kirimana a Ford ki a Kar Kraft o Dearborn, Michigan, ki te whakarerekē i ngā Cobra Jet Mustang e whā ngā tere ki te whakaae ki a ia. Ko Kar Kraft he whare whakamātautau motuhake a Ford i mahi hei Hangarau Waka mo nga Waka Motuhake a Ford. I hangaia e Kar Kraft te GT40 MKII tuatahi (ko te toa o te 1966 24 Hours o Le Mans
) me te hangaia, ka hanga i te GT40 MKIV (toa o te 1967 24 Hours o Le Mans).