No Durango EVER came with performance R/T heads or a special cam. While there ARE R/T heads available, and you CAN use them on the Magnum motors, they are Mopar Performance parts, not included with the stock R/T Durango.
The 2000 simply had a different PCM tune and muffler. That's it, and why the specs only reflect an additional 5 HP.
As for what causes pinging, as I mentioned in the other post, not quite accurate. Hshock, did you write that or cut and paste it from elsewhere? It is wrong. Sorry
IndyDurango