Still need a little help understanding the control the pcm has over changes made to improve performance. 2004HD 6.0. Simple upgrades to improve performance. I've added a K&N CAI system, true dual Flowmaster 50s, replaced plugs (AC platinum), and replaced the plug wires (Bosch). Is it necessary for a pcm reprogram to take full advantage of the changes or does the pcm recognize the changes and make the appropriate moves on the fly?