360 vs 340 torque converter

273 said

Cast crank 340 rotating assembly weighs different than a 360's and 5.9 is also different from a 340 & 360 so they take different amount of weight to be balanced only internally balanced engine can swap.

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X2 "Externally balanced" does NOT mean that two different cid engines have the same "external balance."

A good case is the 360 LA VS the 360 Magnums, both externally balanced, and both are different weights, as I understand it.