Originally Posted by northiam
When selecting a solid cam the manufacturers quote advertised duration and lift. Some quote their figures at 0.020 lobe lift and others do not make any reference to their advertised numbers. Do advertised figures count or should one only look at 0.050 numbers? As an example the crane F238 advertised readings are far bigger than the F246, (overlap 89 compared to 71deg)! Also valve lift would always be less the lash clearance!
Like benx said, the 50 thou duration is important, as that is when the airflow realy starts, or is comparable between camshafts. Also, dont worry about subtracting the lash to look at lift on solid cams. Look at the lift that is advertized by the cam manufacturer. Most people have an idea of what sort of lifts they are after for their application.