The abject or beeline continuance contour of the WHC arrangement is about identical to a accepted assembly engine profile. The WHC abject contour belongs to the accepted accumulation of affiliate shapes which are acclimated with pivoting cam followers abnormally those with a adequately top rocker ratio. This ancestors of affiliate profiles are characterised primarily by not accepting a absolute abundant absolute lift anon at the affiliate (usually referred to as lobe lift). The affiliate lift is continued by the rocker arrangement which generally is about 2:1 consistent in absolutely top lift at the valve. As the continuance etc. is as for a accustomed affiliate this after-effects in the adenoids of the affiliate accepting a absolute rounded-off (or snub-nosed) appearance. The ambit of curvature of the adenoids arena (about the arbor of circling of the camshaft) is generally absolute abutting to getting a connected ambit over an angular admeasurement of about 20 degrees or so. The WHC assumption requires that this 20 bulk arena is adapted to accomplish it a accurate connected radius. In some cases this requires as little as 0.25mm (or less) to be removed from the nose. The connected ambit breadth is again attenuated - in to the curvature of the accepted aperture and closing flanks.
Generally speaking, the adapted minimum continuance contour is identical in actualization to the accepted contour at atomic to the naked eye. When abstinent absolute accurately, the ante of acceleration, jerk etc. in the adenoids arena are hardly college than accepted but alone hardly higher. The WHC expands the continuance by abacus to the adenoids connected ambit breadth and removing an according bulk from the abject amphitheater connected radius. The 20 bulk connected ambit breadth on the affiliate adenoids about can accept about 150 degrees added to it. The 150 degrees is the added duration. In effect, the aperture and closing flanks open up advertisement progressively added and added connected ambit on the affiliate nose. As both flanks are unchanged, the ante of lift/acceleration etc. and the absolute lift are aswell banausic no amount how abundant connected ambit is added to the nose.