Slow 1/8 with 74 440 dart

What Distributor and coil are you running? If it's mostly a street car you probably want VA. What are your plugs gapped? There are a couple of threads going on the HEI conversion in the Electrical section. I would do that b/4 going to an MSD box unless you have a good known 6AL. Or by E core coil and the Hi Rev 7500 box eliminate the ballast to keep it Mopar. Coil with heat sink $25-35. Hi Rev box about $40. Or same coil, HEI module $20, GM heatsink from Rock Auto $25 and connectors for the HEI conversion. Both cheap and effective.
Here's an example of the 440 that was in my car whenever I bought it. TRW 2266F .030, 75 thou in the hole, .020 shim hg, home ported 906 heads 91cc checked, 292/509 purple shaft the old version, Team G intake 850 dp, T/A 3800 convertor and 391s. It liked 38-40 total timing and 24 initial. Ran a best of 11.91 @111. I do run the MSD Pro billet because it is easier to fix the timing curve.