If you have the wrong dampener and/or flexplate, then you’ll know quickly lol.
Usually, a 6” rod 383 or larger can be internally balanced, via a machine shop, and can use non-balanced flexplate and dampener. A short rod 383 or larger can’t be internally balanced with normal components, hence, the reason for the external balance requirement. I don’t believe rear main seal type has any bearing on the requirement.
Bottom line - the people that sold the motor should know what it needs without any guessing.
Usually, a 6” rod 383 or larger can be internally balanced, via a machine shop, and can use non-balanced flexplate and dampener. A short rod 383 or larger can’t be internally balanced with normal components, hence, the reason for the external balance requirement. I don’t believe rear main seal type has any bearing on the requirement.
Bottom line - the people that sold the motor should know what it needs without any guessing.
