80% of lifters or 80% of lifter sets ( having at least one bad lifter out of a set of 16)? Is a lifter bad if you move it from a hole where it doesn't spin to a hole where it does spin? And what does it say if you have one that doesn't spin and swap it with one that does spin resulting in both lifters spinning?
Lifter “brands” (sets) on the market. Kevin at Schneider cam told me not to run a cam with less than .004 lobe taper.
I did this on my last flat tappet break-in. Mark the lifters with a sharpie and roll the cam with light oil. Can't really think of a good lifter rotation check with the valve springs in play without wiping off the cam lube though.
That's almost NEVER the cause in my experience, and I do this every day. In my experience 99.9% of the time, its incorrect machining on the lifter face. I have the equipment to remachine lifters in my shop, and I will not install ANY lifter that I dont remachine first. In the past year alone I have probably done over a 1000 of them for customers. It's not the oil, it's not the lifter bore, it's not lobe taper. It's not break in teqnique, Its lifter face machining, almost allways.
This: "I will not install ANY lifter that I dont remachine first."
My son found a solid roller equivalent for my street engine.
