Once the heads are torqued to spec (65 lb-ft in our case), install and adjust the rocker arm/pushrod combo. With the lifter on the cam lobe’s base circle (piston at TDC firing), twist the pushrod with your fingers as you tighten the rocker arm nut. As you start to feel drag on the pushrod, you’ve reached zero lash. At zero lash, tighten the rocker arm nut approximately three quarters of a turn more.