re: post #41, relevant, only based on an earlier post inquiring about the EGR valve seal integrity. I probably shouldn't have replies to two posts without identifying them.
post #42: TDC does coincide with the flywheel marks.
post 42~46: The valves were not removed from the head, but the cam was left in place the second time and it was rotated to assure that all the valves opened to permit visual inspection of the soot buildup condition on the stem side of the valves.
I don't hear the tappetty-tap of the lobes that I'd expect with followers that don't pump up, and .020 would make noise, but wouldn't reduce the air flow all that much. I had flushed the followers as best I could the first time the cam was off (submerged in 5w20 and stroked to displace crud oil and draw in the 5w20). None of the followers failed to exchange the oils. I believe all are functioning and holding pressure.
Aftercooler: That is where I'm heading today. The complete obstruction of the EGR air flow last night resulted in a reduction to a maximum 1200 rpm (maybe because the engine was cold, but maybe not).
Maybe the issue isn't air not getting in the intake (excess fuel smoke, low max rpm, but good idle) but may be air not getting OUT the exhaust. I've cleaned the turbo from the vanes out and from the head down as far as I can, but a restriction at the scroll could reduce air flow through the turbo just prior to the vanes.
This would be consistent with a number of clues:
Good idle and slow speed smoothness,
Excess smoke at higher rpm,
Lower rpm when EGR is blocked
Nearly stalls when EGR is open
I hadn't thought that last one was more than a 'red herring', but now it may make sense in the continually evolving theories.
Here's this morning's theory and the evidence on which it's based: So much restriction getting into the turbo that there is high back pressure even before the down pipe. So much restriction that high rpm isn't possible.
Air can't get out, so no room for air to get in (Excess fuel can also be insufficient air).
Blocking the EGR air flow prevents another path for exhaust to get out.
Opening the EGR when there is high back pressure before the turbo, puts too much O2 depleted air in the intake.
I'll write back within the hour with the report if leaving the EGR cooler pipe completely off made a difference.