Installing new timing chain on a 318, questioning the oil slinger

It is an oil slinger. It is slinging off the oil that come in contact with the back of it. You could also call it a deflector, both are correct.

The Pontiac V8 is veeeeery similar in the front to the SBM. Cam is retained by a thrust plate; fuel pump is driven by an eccentric bolted to the cam sprocket. It doesn't use the slinger & they do not leak oil in that area.