chrysler changed the 3.9, 5.2 and 5.9 in 92 with the magnum series of engine. chrysler actually changed something with it's cam grinds to allow the egr to be deleted.
same goes for the jeep 2.5 and 4.0(ended in 06). and no chrysler has had vvt except for the new pentstar and the 5.7 hemi(i think)
if you want some reading visit this web site
Allpar has Dodge, Chrysler, Plymouth, and Jeep car, minivan, and truck information