Back in the seventies as I remember. There was a big oil/gas crisis during about 1975 and gas went up to like $1.40 or somewhere around that Price. The talk about the end of the US oil supply being calculated and the end of the US Auto industry. Cars suddenly went from the Muscle Cars of the late 60's and early 70's or the Mach I Mustang with a 429 Cobra Jet to the Mustang II 4 banger. It was around the Ford or Carter era. I was always under the impression it had more to do with using up the Mid-East oil and saving our own oil for the dry days to come but that was just me.