Billets are more expensive than forgings basically because the forging allows less time to finish the cranks vs hogging the shape out of a large piece of steel, (Billet).
Brian is correct about the grain flow too.
The billet does allow a vast array of different main/stroke/rod journal sizes vs the forging which will have only so much material in any one direction.
A Forging must have two key ingredients to be successful:
1) Clean steel of the correct material type like 4340.
2) Proper machining of the forging in all dimensions at all parts of the crank and the right oiling scheme to survive high rpm loads.
You get both of those things for your $1100.00 and you have a great part.
JMO
Tom V.
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"Engineers do stuff for reasons" Tom Vaught
Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward.
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