Well.... @#$%
First the broken springs
Clicky - High Speed Miss Thread
Then the worn valves
Clicky - Head Rebuild Thread
I finally got the motor back together. To set the preload on the valves I followed this procedure. All the polylocks had been undone - not torqued - since the rebuild, so all the lifters should be bled out.
1. twisted, lifted, pushed the pushrod while tightening the polylock.
2. Immediately when resistance is felt - zero lash.
3. Add 1/4 turn preload
4. Tighten polylock and set screw.
For most of the lifters, there was a noticeable resistance while turning that quarter turn. For a few of them, there was no resistance at all. I still turned it the quarter turn and set it. Initially there was quite the sewing machine sound on the passenger side while idling cold. It would decrease when warm but still rattled.
Went out for a drive and the miss above 3000 rpm is back. I'm not even at WOT. When I just creep up to 3000, it starts to miss.
Thoughts: Something wrong with setting those lifters' preload. I'm planning on doing a CLOSE inspection on the valve train tomorrow and doing a hot set of the preload with the engine running tomorrow to make sure the lifters are pumped up correctly.
I have the Howard's brand link-bar lifters. Hydraulic roller retrofit on normal cam in a non-roller block. Nowhere can I find the recommended preload for these. I think they are made by Morel for Howard's.
Blykins, what do you set your roller lifter preload to?