Scotty, this is mainly for solid rollers, or djustable rockers.(pre 97 engines) where you have to set your preload onto the lifter.
when you are tightening down the rockers in proper order. ok. you are on a certain cylinder. with your fingers you are spining the pushrod...and tightening the rocker nut. as soon as the rocker stops the pushrod from able to be turned...you are say at zero. for the specific preload of the lifters.. say they are OE-R's..you would then tighten down the rocker an additional 1/4 to 3/4 turns instead of stock. then tighten down the retainer set screw to keep tension on the locks.
with the new shaft style that are in our cars..there is really no way of setting it as the factory torque specs for the rocker bolts...they are not adjustable.
so you dont have to worry about the specific preload unless you have adjustable rockers....in our cars.
hope this helps....
