I have a LTD with a 10 cm displacer chamber sitting on top of the PC
monitor. Out of curiosity I timed the rpm several times sometime after
shutting down the PC. The rpm dropped from 40 rpm to 22 rpm and the
last timing was at approx. 20.7 rpm and the engine stalled shortly
after completing the last turn. The next test will to be making a
controlled heat source to see what the lowest speed can be attained
and sustained.