Pink wire can lock in base idle reduction or effective advance in cranking on a Duraspark II.
On a TFi, 'administritive' solid state programed ignition, the Knock sensor could SPOUT in or out total advance.
Ford were slowly moving from simple analog Presolite/ Autolite systems with no electronic module and base centrifugal advance with maybe a vac advance added to the same basic Autolite with Solid State triggering replacing the points.
Next step wasn't vacuum retard on over run, or Ported, Speed or Manifold vacuum variants, but the pink wire micro pause by dwell control which gives around 5 degrees base advance. For example, the 79-81 Turbo 2.3 Carb didn't use boost retard by a second line off the other side of the advance canister, but by dwell control and secondary null switches which trimmed total advance by the vacuum lines. The Diode spark sustain valves were designed to delay advance or retard, rather than trying to program it into the vacuum canister.
The TFi 1983 Mustang 2.3 EFi Turbo used totally solid state ignition administration. It was effectively a Brown Box Yellow Strain Duraspark III, a gutted Duraspark with a totally dynamic dwell control. 80-84 EEC III with another wrinkle of leading edge control programed in by Electronics technicians.
The Duraspark II in a turbo 2.3 carb had no boost retard line, it did the ignition advance and retard by dwell control and some sustain and null knob systems which blended from the manifold vacuum tree to get a Programed ignition curve using it's existing emissions devices.
You can do the same. One system which is doing this is Kim Fixes Things and Buff Del Campo's 1972 Valiant 225 2bbl Turbo.
Its going to use the stock pre Solid State Presolite distributor and use the old advance unit to tailer boost curve retard under boost.
Huge McInnes in his early blow through systems showed the various ways of on boost advance retard. Normally, a second line and the common emission era Presolite advance billow can control and map advance under trailing throttle and wide open throttle. The specific way to control air fuel and advance is to just use the crutches the Feds forced Ford, AMC and Mopar to avoid rich and lean conditions during the Federal Test Procedure. I'd just use the stock Vacuum Operated Throttle Modulator ( a dampener) the advance retard on over run by Ported Vacuum, the diode Sustain valve, the pink wire, and the reverse power valve to jumper the type of advance the distributor vaccum canister sees. The emissions parts are still around if you go through my FoMoCo VECI item list from the 2.3 Liter M81 McLaren Mustang Turbo rebuild on Four Eyed Pride. Something like 85 items. The late Stormin' Norman gave a great way on how to recreate a Vacuum Emissions Component Instruction list to govern the Federal control of the ignition and air fuel delivery systems.
I'll post a link when I get time.
On a 2.3 Turbo Carb Mustang, the whole advance was controlled by a stock Blue Strain Relief Duraspark II
A two element system controlled the Manifold, Ported and Spark lines. The metal maVV nifold hook up jumpers the boost pressure from the turbo.
A manifold tree at the front of the engine relayed the rubber lines to a vast array of Sustain valves, in and partial signal return vacuum Diodes and crazy specific emission valves from an 83item VECI valve and emission part list.
A five tree take off rubber Vacuum line manifold by the Duraspark II module/ Screen Washer reservoir with three to five null knobs electrically controlled boost retard.
RNR#1 and 4 are the metal vacuum lines.
MAN PLNM is your vacuum tree at the front of your engine.
SPK RET is the set of switches by your washer res.
That's all FoMoCo did to tailor an advance curve.
Meela's post is the best on the system basics
The whole system has 83 to 93 parts, but any guy can make spark trim with Duraspark II and a turbo or Blower work with about seven parts.
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http://vb.foureyedpride.com/showthread.php?183892-1979-2-3-turbo-vacuum-lines"
