Gary Lewis Posted November 12, 2019 Share Posted November 12, 2019 ^^^^What he said Gary, this needs to be the DSII tutorial. Bill is thorough and concise in his description of the components and function of the system that powered hundreds of millions of Ford vehicles between the mid 1970's to 1990 Bravo Bill! Bill/Jim - We may have the right place for it. Please take a look at Documentation/Electrical/Ignition and go to the Ignition Simplification tab. There we have an explanation up top and then two more tabs: DS-II and One Wire. But Bill's explanation doesn't quite fit neatly into the DS-II tab. Instead, I suggest we put the first three paragraphs of Bill's post up top, before the DS-II and One Wire tabs. And then the last paragraph would get split between the two tabs. I think on the DS-II tab we'd need to include the appropriate schematics from the EVTM, which is easily done. And on the One Wire tab Bill's explanation about where to get the switching signal for the relay fits perfectly with the diagram. Thoughts? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 12, 2019 Share Posted November 12, 2019 Bill/Jim - We may have the right place for it. Please take a look at Documentation/Electrical/Ignition and go to the Ignition Simplification tab. There we have an explanation up top and then two more tabs: DS-II and One Wire. But Bill's explanation doesn't quite fit neatly into the DS-II tab. Instead, I suggest we put the first three paragraphs of Bill's post up top, before the DS-II and One Wire tabs. And then the last paragraph would get split between the two tabs. I think on the DS-II tab we'd need to include the appropriate schematics from the EVTM, which is easily done. And on the One Wire tab Bill's explanation about where to get the switching signal for the relay fits perfectly with the diagram. Thoughts? It's your baby Gary. I defer to your knowledge and familiarity with the back end of the forum I think we also need a schematic for the HEI. Maybe something like this: XXX Link to comment Share on other sites More sharing options...
Gary Lewis Posted November 12, 2019 Share Posted November 12, 2019 It's your baby Gary. I defer to your knowledge and familiarity with the back end of the forum I think we also need a schematic for the HEI. Maybe something like this: XXX Bill - Your thoughts, please. They are your words. Jim - Why isn't this schematic from the One Wire tab enough? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 12, 2019 Share Posted November 12, 2019 Bill - Your thoughts, please. They are your words. Jim - Why isn't this schematic from the One Wire tab enough? Because frankly, though I had seen your diagram, I hadn't looked at that tab to realize it was already there! Link to comment Share on other sites More sharing options...
Gary Lewis Posted November 12, 2019 Share Posted November 12, 2019 Because frankly, though I had seen your diagram, I hadn't looked at that tab to realize it was already there! No prob. I thought you were saying something more was needed. Anyway, let's see what Bill says. If he agrees then I'll do some work in a day or two on using his words to explain how the wiring works on these trucks and what is needed to convert to DS-II. Link to comment Share on other sites More sharing options...
85lebaront2 Posted November 12, 2019 Share Posted November 12, 2019 No prob. I thought you were saying something more was needed. Anyway, let's see what Bill says. If he agrees then I'll do some work in a day or two on using his words to explain how the wiring works on these trucks and what is needed to convert to DS-II. Gary, it needs to emulate the EEC feed, W/lb and R/LG wires both need to be connected to the relay. The diagram as you have it may "drop out" the relay when cranking. The ignition wiring on these was a solution to providing a solid battery voltage feed under cranking and running for the EEC, or to provide a coil resistor for the DSII system. Link to comment Share on other sites More sharing options...
Gary Lewis Posted November 12, 2019 Share Posted November 12, 2019 Gary, it needs to emulate the EEC feed, W/lb and R/LG wires both need to be connected to the relay. The diagram as you have it may "drop out" the relay when cranking. The ignition wiring on these was a solution to providing a solid battery voltage feed under cranking and running for the EEC, or to provide a coil resistor for the DSII system. Bill - Excellent catch! The way I show it the engine won't fire until you turn the key to Run. I'll fix that and work on that tab later. Thanks. Link to comment Share on other sites More sharing options...
Danny G Posted November 12, 2019 Author Share Posted November 12, 2019 Gary, it needs to emulate the EEC feed, W/lb and R/LG wires both need to be connected to the relay. The diagram as you have it may "drop out" the relay when cranking. The ignition wiring on these was a solution to providing a solid battery voltage feed under cranking and running for the EEC, or to provide a coil resistor for the DSII system. Gentlemen you are a wealth of knowledge and I am glad this discussion is leading to some documented guides that I and others will have all they need to do this swap to DSII. The gentleman on FTE had these final 3 tidbits to say. What are your thoughts Bill? "DS I is a true HEI system that adjusts dwell with engine RPM (DS II is fixed) utilizes a crank retard (DS II does not) and feeds a full 12 V to the coil as opposed to the resisted down voltage of DS II. DS II is not true HEI System like GM's HEI system whereas DS I is." "The install for DS I is very simple two wires need to be switched around and the centre tab on the male dist connector trimmed of connector (it is clocked differently than DS II but is clocked the same as the crank retard module." "you can use the TFI coil with DS II with no issues. The TFI coil is designed to run at much higher power levels than what DS II can generate and the Ford TFI coil falls within the operational tolerances of modern (1980 and up) DS II boxes." Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 12, 2019 Share Posted November 12, 2019 Gentlemen you are a wealth of knowledge and I am glad this discussion is leading to some documented guides that I and others will have all they need to do this swap to DSII. The gentleman on FTE had these final 3 tidbits to say. What are your thoughts Bill? "DS I is a true HEI system that adjusts dwell with engine RPM (DS II is fixed) utilizes a crank retard (DS II does not) and feeds a full 12 V to the coil as opposed to the resisted down voltage of DS II. DS II is not true HEI System like GM's HEI system whereas DS I is." "The install for DS I is very simple two wires need to be switched around and the centre tab on the male dist connector trimmed of connector (it is clocked differently than DS II but is clocked the same as the crank retard module." "you can use the TFI coil with DS II with no issues. The TFI coil is designed to run at much higher power levels than what DS II can generate and the Ford TFI coil falls within the operational tolerances of modern (1980 and up) DS II boxes." I'm not Bill, but DSII definitely DOES use crank retard (iirc 3°) What purpose does the white lead of the module serve??? The high winding ratio and resistance of the DSII coil will be saturated and become a filament without the resistor. If the coil reaches full potential, who cares if it is limited by the charging window or a resistor? 45kV is 45kV. There's nothing 'higher powered' about the TFI coil. There is a difference in the load that needs to be switched. As for DS-I, it was needed for Cali emissions, not performance. And it was discontinued because of unreliability Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 12, 2019 Share Posted November 12, 2019 I'm not Bill, but DSII definitely DOES use crank retard (iirc 3°) What purpose does the white lead of the module serve??? The high winding ratio and resistance of the DSII coil will be saturated and become a filament without the resistor. If the coil reaches full potential, who cares if it is limited by the charging window or a resistor? 45kV is 45kV. There's nothing 'higher powered' about the TFI coil. There is a difference in the load that needs to be switched. As for DS-I, it was needed for Cali emissions, not performance. And it was discontinued because of unreliability Don't believe me... Ask Bill (Numberdummy) over on FTE. He was a California parts counter man for 38 years, during the heyday of the Bullnose. Link to comment Share on other sites More sharing options...
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