Internally Balance Cast Crank?

Ummmm, how did we get to 360 cranks, again? lol

IIRC the early 340 pistons were about 742 grams.
And the hypers are about 585?

Since we got to talking about 360s; Mine is a 71, I installed the KB107s which are 502grms. I installed rods from an early teener with the bushed pin holes. These carry the same casting number as the early 340s. I had them evened up and sent everything out to be balanced, including a neutral balance factory teener flywheel,and the 360damper. When I got it back, the damper was untouched, and the flywheel had three small holes drilled into it.
This engine regularly goes 7200, and cruises in O/D at 2200.It is very smooth and revs really quick.I like it!