Which Harmonic Balancer To Use?

If the dampener is off,does it have a weight side to it,and if you have the tranny that the motor was attatch too is the convertor weighted.You most likely have a 440 cast crank dampener with externally balanced dampener.How thick is the dampener?Is it like 2 inches thick and what side is the timing mark on?Whats wrong with the old one and are you upgrading the dampener?Mrmopartech