Originally Posted by Trashed666
So my first time measuring Pushrod length, I have my cylinder #1 TDC lifter on base circle, push rod length checker in and it takes 17 turns to get to zero lash giving me a base pushrod length of 7.65. So I add the .035 Johnson recommended pre-load for the 2116LSR lifters giving me total length of 7.685 for push rods. The cam came with the recommendation for 7.4 pushrods. It also takes approximately 1/4 maybe a little more of a turn to get to 22ft/lbs from zero lash which seems low to me.
I am curious as to the difference in the recommendation and the actual measurements. Could it be the recommendations are for a normal block not a re-sleeved superdeck from ERL, Also using PRC 255 heads that have been milled to 69cc, and minimally resurfaced. Would the difference in stock block vs superdeck, aftermarket heads, and Johnson 2116 LSR be whats accounting for difference in the recommended length and measured length?
The recommendation is probably for OEM style heads/lifters. The aftermarket castings often have a taller rocker mount so you end up with longer pushrods. The lifters don't require as much preload, plus they could have a different cup height, both of which would skew the pushrod length as well.