So I have my 350 bored .30 over, a brand new 383 kit from eagle that is balanced. I'm looking for a new harmonic balancer.

My research shows that 400sb is externally balanced. Since it's a "400" crank does that mean it needs to be internally/externally balancing... balancer? Or do I pick the "Engine Balance: Internal" on summit?

 

Nevermind... Straight from Eagle Specialty Products' website:

"You can also notice the contents of the kit. An internally balanced kit will not include a harmonic dampener or flywheel because they are not required for balancing - use whatever brand you like. Externally balanced kits will include a harmonic dampener and/or flexplate as needed. If we provide a harmonic dampener and flexplate it will be a O.E. style replacement, not SFI approved. If you building a high horsepower engine, internal balance is preferred anyway. Internal balance is better for longevity of parts and fatigue life."