340 ballance

Your 340 crank shaft can be ID if its a forged or cast crank by the vibration dampener.The biggest item to look for on the VD is a off set weight on the front of the VD.If its there,its a cast crank,if its not its a forged crank.Cast cranks are externally balanced,forged,internally balanced,and the VD is fully round with no external off set weight that you can see.The ID numbers to ID your motor are on the front of the drivers bank,just under where the head and block meet,scratch the paint off or buff the area and you will see it,then I can tell you the who,what and where of your motor.Depending on the year,you can have either crank,mrmopartech