Around here coronets we’re hardly sleepers….Mom had one with a 440 in it and I got to drive it on occasion but I wouldn’t have called it a sleeper.
I didn’t know you got valients over there so I learnt something!!! 
https://www.youtube.com/watch?v=RoiWpJLokEc
Not a sleeper either but I thought it might interest you.
Nice daily driver Volvo Amazon on that video...

Darts and Valiants were the most sold American cars in Finland at 60s and 70s, I've had some as DDs. Coronets were mostly 4 doors w/ 273 or 225 because of Finnish tax laws and BB V8s in general pretty rare. Nowadays it's of course different as they are classics and import from abroad has been free long time. Well, it was free always, but idiotic taxation made it ridiculously expensive.