Edelbrock, TrickFlow rocker question
I asked HS about this in the past. The standard HS rocker setup for LA heads will work on LA heads with longer than stock valves (they recommend 0.100 to 0.200” longer than stock as I recall) or the Trick Flow heads using shaft oiling up the pedestals. Trick Flow heads come standard with longer than stock valves.
The HS Trick Flow HS rockers are different in that they are designed for pushrod oiling. The adjusted is drilled to receive the oil from the pushrod and the rocker body is drilled different to receive the oil from the adjuster versus having the oil hole drilled to feed the pushrod cup. You can use these Trick Flow rockers on other LA heads if they use pushrod oiling and the longer than stock valves recommended by HS.
The Edelbrock HS rockers are different because Eddy either does not use the longer than stock valves as HS requires for the standard set or the Trick Flow set or perhaps the Edelbrock heads have the shaft placed a little differently requiring a different rocker arm. HS created a different rocker body with a shorter length nose which I believe is something like 0.050” shorter.