rocker arms adjustment

The preload on hydraulic lifters is supposed to be between .020 and .060". If you know the number of threads per inch on the adjuster screw you can calculate how many turns you need. Most of the adjustable rockers use a 24 thread per inch adjustment screw so: 1 divided by 24 = .041" per turn. I like to set the adjustment in the center of the range at .040" - or 1 turn after the slack is taken out of the pushrod. Makes it a little easier to understand.