What is the difference? For some reason its confusing the hell out of me. If i get my crank balanced does that mean its internally balanced? I need you guys help on this one.

 

Externally balanced engines are balanced as an assembly with counter weights on the flywheel and/or the balancer. They scrapped this plan because it was a pain and not as effective as balancing each component seperatly. That is the easy way to explain it. Basically, a 400's crank, flexplate,and balancer are unbalanced until all assembled with the counter weight. On a 350 (& 305) the crank, balancer and flexplate/flywheel are all balanced seperatley so, therefore the assembly is balanced. That is why you can bolt a manual flywheel where anautomatic flexplate was on a 350 and not have any problems, not so with the 400. Ther, I think I've gotten that issue about as clear as mud for you. LOL