Well, my question is regarding not being able to run it at 4K, it quits when throttled down that low. The lowest it will stay running is ~5000. The temp gauge is only used to verify all cylinders are firing, nothing more. I did check all the valves last night, and snugged up a few that were over .004 and everything has a nice sheen of oil on them.
Here is a video of it running, listen to it modulate the speed.