[Woodz428]

As has already been posted, it was indeed main bearing loading that Ford was re-distributing. I would have to look at the early order, but think it had to do with not having 2 firing pulses (one after another) on the same main. The other comment about the early H.O. cam is also correct, the original cam used in tests was a 351 marine cam. That neccesitated the 302 change, although the initial change made in the new (at the time) 351W was main loading.