340 engine (flywheel)

Just neutral balance the cast crank, they are close as is and don't require much. They are lighter than the Forged crank and unless your going to run boost, Nitrous, or doing 8k clutch dums it will take anything the block can withstand.

My 72 cast is internally balanced behind a TKO with a McLeod SFI Flywheel and Jegs SFI balancer, both neutral.