how to tell if 440 is externally or internally balanced?

[SirChandlr]

its a 74 440, how do i tell?

[tactransman]

Forged crank- internal balance, cast crank- external balance.
'74 should be a cast crank.
check out this link: http://www.moparts.com/Tech/Archive/bb/50.html

[Chryco Psycho]

how thick is the damper , 1" approx is steel , 1 3/4" is cast

[SirChandlr]

  damper looks to be 1"
 l

[ShelbyDogg]

The dampener would say "use with 440 cast crank only" on the front and look like it's weighted on one side.  The torque converter would also have some weights on one side or have a drilled Flywheel with 3 BIG holes in the backside.If the engine was balanced by a machine shop, they might have installed a forged (thin) balancer though.