"On the crylser system, wouldn't it just retard the timing past the knock point, and thus effectivly have a pressure retard? Does not having vacuum affect the knock retard part? If it's in a "limp home mode" type thing, would it still consider the knock,..."

I'm no expert on how the V/C ignition works, except for what I read in that Vacuum-Plugging thing I copped off the 'net and posted here as a NOx-dropper (see link in my post higher up). Those aren't my words, just a minor edit.

But my hunch is yes, the knock-sensing retard will still work, and that only the initial off-idle huge advance is eliminated when the vacuum line is plugged (and reattached to avoid questions from the curious types).

The diaphragm capsule on the box is still there—and anyway, it's not a smog device like EGR. So if plugging the line actually has a good effect on reducing emissions (as your dyno test proved) who could argue with it — and on what grounds?

--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.