Two more things seen less often.

Saab 96

Ford Corsair


They have a V4 in common and it’s a Ford one in each case. So, glue two together and you get a V8. Or maybe not. Ford, you see, permitted themselves the luxury of two V4s of about the same size. The Corsair, being from Ford of Britain, had the Essex V4 (which was indeed made in Essex) while the continental Saab had the smaller continental equivalent, the Taunus V4 which was originally designed for an American model and then passed on to Ford Germany who later grew a V6 out of it .