Exactly,now just what is the published rocker arm ratio for a GMC? Anyone ever see it in print?I never have.
I tried a variety of rockerarm angles to see how it affects lift.Having the rocker parallel to head surface at mid travel,goes over center the same distance when opened or closed.And the more stock approach,where the rocker is fairly parallel to the head surface when the valve is closed and goes over center when opening.Little difference in lift, about .005 or so.More important is to keep the rocker tip centered on the valve stem for least wear.
