[lovehamr]

The idle thing makes absolutely no sense. Unless the hole went under the butterflies there's no way that they would affect the idle, the holes are above the entire idle circuit.

This: "These were early design booster signal control calibrated vents." actually makes a little sense. At least they are in a position to affect booster signal. Why they would need it I have no idea. Seems like it'd be better just to use different booster venturies.