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One of the gears on the aerovee turbo oil pump has a punch mark on it and I'm curious as to the significance of this. Anyone know?

If it was manufactured in a government factory, it's likely someone's nephew needed a job.

It's a timing mark. But I'm not sure what the timing set up might be - or if it even matters on that application. If you search the term:

spur gear oil pump timing mark

you will find discussions on the topic - when it matters and when it doesn't.