1969 Valiant, 340...TCI 727...8 3/4 w/3.55

1972 manual equiped 340's were internally balanced but the 72 automatic cars were phased in with the externally balanced engines then all became externally balanced in 73
Quick look at crankshaft dampner tells the story. If dampener has offset lobe on back it is external,if smooth on back it is internally balanced.

Oldschoolcuda