U20 cam cover ventilation inlet differences

[19692000survivor]

I have had (4) U20 engines. (3) have an inlet for ventilation hose like the one pictured on the bottom left. The other is like the one on the right? Why the difference? Was it a change on later models?

[JT68]

The little stubby one was the early style, there isn't much holding the hose on. Nissan revised it to the more secure 45 degree, so those came later.

Functionally there is no difference (unless the hoses falls off)

[19692000survivor]

I know the hose fits way better on the later cover vs the than the earlier version. Thanks for the explanation. Rick