Reward
Hmm, the motor I've got in my dart has one like that. it's out of a '67 belvedere. So it's one of the earliest 318's.
Though, it's utterly useless, since my 318 has something wrong between the crank keyway, the harmonic balancer, and the timing tab, where it only runs with the timing mark about 120 degrees before the timing tab. (put a timiing light on it while it's running, and the timing mark is down by the k-member.) Which I think is kinda strange.