On 1992-1995 Magnum v8s the PCV valve discharges into the passenger side of the "beer barrel" intake manifold that has an internal center divider that nearly closes off the plenum into two sections for 4 cylinders each. I suspect this sends more oil vapor to cylinders 2, 4, 6 and 8 which may cause more carbon deposits on those cylinders.

The Magnum V8 intake manifold also has an IAT sensor mounted in cylinder 1 intake runner and i have wondered if using that threaded hole whether all the PCV vapor could temporarily be injected there as an experiment to see what happens to cylinder 1 alone from getting all the "gunk" to burn.

During the experiment the IAT sensor could be located somewhere else, like many owners have already done to slightly advance or retard ignition timing.

With todays cheap video boroscopes it is easier to look into combustion chambers and the half inch threaded hole on Magnum V8s cylinder No 1 intake runner also allows an easy place to look at the backside of the intake valve, or even watch the injector spray pattern.