I can certainly feel the difference between the Mopar Performance PCM on my 1995 Magnum 5.9 V8 and the stock PCM.
I guess that means that ignition timing was pretty retarded from Mean Best Torque.The MP PCM supposedly advanced the ignition timing up to 12 degrees at some points in the RPM/ throttle opening table.

I certainly remember HUGE complaints from both 5.2 and 5.9 V8 owners who took their trucks in to dealers and got the “Death Flash” in the 1997-2001 period.