School me on W2 heads.
The fact of the matter is that when they (Engineers) were told NOT to put W2 heads on the test engine because the head is NOT being considered for production use, they did anyway and found that the head would pass emissions for the time (year) and could be used in production. More power was found. I do not know what the dyno told them.
The head was never slated for the truck or production use. NEVER!
The head was designed from the on set to be a racers head. PERIOD!