1972 Dodge Colt

You keep repeating small crank and big crank. So is this a cast crank engine?
Forged.
The "BIG" crank was 92 lbs. on my scale.
The "Small" crank was 75 lbs.
Here are the center counterweight pictures.
When I was a kid decades ago, these were called Truck Cranks.
Here they are side by side, look at the center counterweight.

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