It's not a GM designed engine, with overhead cams, reached a dead end....wikipedia.

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Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid. Albert Einstein

Swim upstream. Go the other way. Ignore the conventional wisdom. If everybody is doing it one way, there’s a good chance you can find your niche by going exactly in the opposite direction", Sam Walton.