489 Case Moldings Different

[72DMag]

My apologies if this has been discussed already but I was unable to find it.

Why are the moldings for the 489 cases different where the numbers are stamped? Is it because of the year? Small yoke versus large yoke? Is there any integrality differences (one stronger than the other) when racing?

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[Dana67Dart]

Can't say I have ever seen one with the indent

But most likely it was an improvement for oil distribution.

Some ford 9 inch have dimples in the hump of the case, my understanding they aided in oil distribution