Wilbur46, if you will go back and check Leo's book you'll find that your original conclusion about what Leo was trying to say was indeed correct. Leo clearly states that Headrick advanced/retarded lobes in order to take advantage of the other part of the siamesed port effectively acting as a larger plenum.
Evidently,this view does NOT coincide with CNCdude's view citing compensation for camshaft twist as the reason for lobe advancement. I offer this not as an endorsement for either view, but rather to point out that it is indeed two differing views on the subject, thusly keeping the record straight. I'll leave it up to the individual to which view he'll choose to subscribe, as both views have merit.
