Are you guys suggesting to run multiple turns of preload? That has always made the car run horribly, and occasionally bend valves. My vote is for crappy parts. I have a Comp set of lifters in my truck that there are two lifters that will clack like a machine gun here and there, One day its fine, 3 days later will clack, 2 days later will go away for a while then come back a couple of days later. The clacking begins an ends on start-up. I have isolated them dis assembled them and nothing there, just in my opinion a poor valving design, a plate instead of a steel ball. Been like this since 2003.
Agree with this, .080-.090 has always ran bad for me when engine is cold, always set them .020-.030 from the clip. Maybe it is thick oil, high oil pressure that can't bled down. How about a spacer for the plunger to limit the travel? I know stock motors never seem to be an issue, aftermarket cams, lifters and heavy valve springs do. You would also need to be sure that the piston to valve clearance is more, and valve spring coil bind is not an issue if you want to run them .090 in the lifter, or bigger problems are going to show up.
