I would say that most cars built in the mid to late 50's will cruise all day at 70 Mph.  So, that is 65 years ago.   I have a 57 cadillac that will prove it.   My 68 Olds Delmont 88, with a 455 and 2.56 : 1 rear end ratio will cruise at 80 mph all day with out issue.  Proved it 2 summers ago on a 900 mile trip to Denver. ... View more

Don't forget Cadillac in the 390 list.  1959-1963.  In addition, you could add another entry with Cadillac 429 and Ford 429. ... View more