I need some help figuring out exactly how hydraulic lifters work. I know that there is a plunger that the pushrod sets in and that it slides into the lifter when we preload it. But why can we use different amounts of preload? 1/4 to one full turn after zero lash. Does that not affect the overall lift we are getting out of the cam? Or does it just set the depth of the piston into the lifter and that stays constant. In my head, I guess I thought that the lifter pumped up and pushed the cup up in the lifter, but I'm not so sure now.
Yesterday, I readjusted my lifters. Initially, I had adjusted the lifters while the engine was running to 1/2 turn in after they quit making noise. Then I read on the Comp and Crane cams websites how to do a static preload on the lifters while the engine is off. That is what prompted me to redo mine. I found out that even though I had adjusted the lifters 1/2 turn after quiet, that actually in a static situation, they were all adjusted to zero preload. Which means that I had to tighten down the lifters an additional 3/4 to 1 full turn, approximately 7/8 to be on the safe side, to get the required preload. Did I increase the lift I am experiencing or is my pushrod just further down into my lifter?
My car sound different to me at idle and it seems to run better than ever. What do you guys think about this?