It's always been interesting to me how all of the GM divisions got to develop their own engines, and how it sometimes looks like they intentionally didn't talk to each other. The Buick has very little similarity to any other GM engines of the era. The Olds/Cad type design was pretty generic for the time, and, of course, Chevy and Pontiac did their own thing focusing on performance. It seems like a lot of time and effort was wasted when they could have consolidated much earlier.