The 1977 Dodge D100 6-cylinder engine likely uses a
gear-driven timing set. There's no specific "timing set" in the sense of a single part number like you might find for a chain or belt drive system. The timing is determined by the meshing of the gears on the crankshaft, camshaft, and distributor (if equipped with points ignition). There isn't a "set" to replace as a single unit.
To clarify: It uses gears, and those gears' relative positions establish the timing. Any replacement parts would be individual gears or related components (e.g., gear sprockets, the timing cover itself). You would not find a pre-assembled "timing set" like you would with a timing chain or belt.
