rburt07 — These new numbers are pretty much the same as your previous ones — still "heretical" mode, of course. This time I compute that you were achieving ~90 mpg. I'd be curious to know what ScanGauge gives for your mpg during these runs, since it seemed (unless I misread your original post) to disagree with my computed mpg. By the way, the ICE isn't a lean-burn engine to my knowledge. It's just that, in heretical mode, it's being forced by MG1 to provide the needed power at lower rpm (and consequently higher LOD) than would otherwise be the case. This has two benefits: (1) greater ICE efficiency since the Atkinson-cycle engine is now being operated closer to its peak efficiency at that power; and (2) lower ICE noise due to the lower rpm. The extra conversion losses (caused by shuttling some of the ICE's output power back from MG2 to MG1) are less than the extra efficiency gains.

Stan