I am now setting my Craigs List searches up to end at 1980 because of the 425/368.
Contrary to popular belief, the 1977 models have greater interior room and usable trunk space than their 1976 counterparts (except Brougham where it is the same). This is covered in factory literature in detail.Respectfully disagree on ride quality which was dramatically improved in the later generation. 75/76 500- 190HP; 425 - 180HP (all engines 4 bbl). Relative to the ~ 900 lb weight differential, 10HP isn't very significant.
JoeNot an owner yet but doing a lot of research because I am probably buying at least 1 and probably 2 for this era. I am now setting my Craigs List searches up to end at 1980 because of the 425/368. I am with Eric - I like the 78's and 79's best. It's a balancing act. They are smaller, still handle well, ooze Cadillac style and have the competent 425 and I believe TH400 making them bulletproof. I love the 74-76's. I prefer them style wise over the 78-79's but when you do that balancing act, I would go with a well sorted 78-79.
EricTake a tape measure to the post 76 cars. I just did and stand by my original statement Greg Surfas
Some comparative data: 1977 De Ville 4-door sedanCurb Weight 4420 lbsPounds per HP 24.5