85lebaront2 Posted January 10, 2019 Share Posted January 10, 2019 Bill - I agree that the white/light blue loses 12v in Start, but it is still fed from the ballast resistor, so should have plenty of power to pull in a Bosch relay. Right? Especially when the white/light blue is no longer powering the coil and/or ignition module. As for what you have "in" Darth on the dash, I do not know. But if I get everything back in this box I'm wrestling with, you'll have pretty parts under the hood soon. You might need to try it, keeping in mind under cranking conditions you will have less than battery voltage available. I do know that 7 volts from the stator circuit will pull in a Bosch relay. On the relay and socket, if it will be underhood, you might want it to be either weatherproof on the plug, or semi weatherproof with a "shroud" over the plug. I have a fair selection of Chrysler relays and their sockets with this style. They were used underhood on the 80s-90s minivans. Either that or the marker/trailer lamps or fuel pump style on these trucks. Link to comment Share on other sites More sharing options...
Steve83 Posted January 10, 2019 Share Posted January 10, 2019 You might need to try it, keeping in mind under cranking conditions you will have less than battery voltage available. I do know that 7 volts from the stator circuit will pull in a Bosch relay. On the relay and socket, if it will be underhood, you might want it to be either weatherproof on the plug, or semi weatherproof with a "shroud" over the plug. I have a fair selection of Chrysler relays and their sockets with this style. They were used underhood on the 80s-90s minivans. Either that or the marker/trailer lamps or fuel pump style on these trucks. I strongly advise against anything marketed as "waterproof" on any vehicle OUTside the passenger cabin. Nothing is. The more seals it has, the more water it HOLDS. https://supermotors.net/getfile/1096921/thumbnail/weatherproof.jpg Bosch relays are weather-resistant on their own, and much more-reliable than older Ford-style relays. If they're inside the factory '92-up underhood PDB, this won't affect them at all: https://supermotors.net/getfile/1117500/thumbnail/170630_wash.jpg Link to comment Share on other sites More sharing options...
85lebaront2 Posted January 10, 2019 Share Posted January 10, 2019 I strongly advise against anything marketed as "waterproof" on any vehicle OUTside the passenger cabin. Nothing is. The more seals it has, the more water it HOLDS. https://supermotors.net/getfile/1096921/thumbnail/weatherproof.jpg Bosch relays are weather-resistant on their own, and much more-reliable than older Ford-style relays. If they're inside the factory '92-up underhood PDB, this won't affect them at all: https://supermotors.net/getfile/1117500/thumbnail/170630_wash.jpg Your opinion, I have had a number of MOPAR products with the shielded relays and never had a problem maybe I should rephrase it to "weatherproof", he is working on a 1986 truck, no underhood PDC, just the crack head wiring on the power distribution (someone loved fusible inks). Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 10, 2019 Share Posted January 10, 2019 Your opinion, I have had a number of MOPAR products with the shielded relays and never had a problem maybe I should rephrase it to "weatherproof", he is working on a 1986 truck, no underhood PDC, just the crack head wiring on the power distribution (someone loved fusible inks). Ok, here's what I'm thinking about. This is a rough attempt, but I need your thoughts, please? What does someone like William need to see? The page would include the EEC wiring diagram, but w/o the red circle. Or, maybe with lots more red showing where the changes should be? And then it'll have something like this, although the power feed needs a fuse. But you get the idea - the EEC bits can be removed the the wiring disconnected at the connectors. Link to comment Share on other sites More sharing options...
Hstrymkrs Posted January 10, 2019 Author Share Posted January 10, 2019 Bill - I agree that the white/light blue loses 12v in Start, but it is still fed from the ballast resistor, so should have plenty of power to pull in a Bosch relay. Right? Especially when the white/light blue is no longer powering the coil and/or ignition module. As for what you have "in" Darth on the dash, I do not know. But if I get everything back in this box I'm wrestling with, you'll have pretty parts under the hood soon. I am waking up from three night shifts, so my mind isn't working real well. Do we not need the power wire to be hot in the start circuit as well like Bill is stating? According to DUI, since I am running a nonfeedback carb, I only need a power wire and a wire for the tach since I will not have a vacuum. Everything else is built into the distributor and works independently of the PCM/EEC. They will include a "plug" that allows the vacuum attachment to be removed. Everything is set up and tuned to my car/engine displacement/cam,etc. I would think that I need a wire that is hot in both the run and the start circuit. The W/LB wire is hot only in the run circuit? I will find some coffee and wake up here shortly. William Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted January 10, 2019 Share Posted January 10, 2019 I am waking up from three night shifts, so my mind isn't working real well. Do we not need the power wire to be hot in the start circuit as well like Bill is stating? According to DUI, since I am running a nonfeedback carb, I only need a power wire and a wire for the tach since I will not have a vacuum. Everything else is built into the distributor and works independently of the PCM/EEC. They will include a "plug" that allows the vacuum attachment to be removed. Everything is set up and tuned to my car/engine displacement/cam,etc. I would think that I need a wire that is hot in both the run and the start circuit. The W/LB wire is hot only in the run circuit? I will find some coffee and wake up here shortly. William Follow the white/l blue wire back in the first schematic. You'll see it's hot in run and in start (through the resistor) I don't know why you wouldn't want vacuum advance. Dynamic timing seems a lot better for power and economy, at least in my experience. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 10, 2019 Share Posted January 10, 2019 I am waking up from three night shifts, so my mind isn't working real well. Do we not need the power wire to be hot in the start circuit as well like Bill is stating? According to DUI, since I am running a nonfeedback carb, I only need a power wire and a wire for the tach since I will not have a vacuum. Everything else is built into the distributor and works independently of the PCM/EEC. They will include a "plug" that allows the vacuum attachment to be removed. Everything is set up and tuned to my car/engine displacement/cam,etc. I would think that I need a wire that is hot in both the run and the start circuit. The W/LB wire is hot only in the run circuit? I will find some coffee and wake up here shortly. William William - Glad you chimed in. And, you reminded me that I need to include the tach wire. Thanks. As for the power feed, Jim is right. The white/light blue wire is powered during Start. And while it is through that resistor, my math says the voltage drop across the resistor will be ~1v. (A typical Bosch relay pulls less than an amp through the coil and with E=IR, it'll be 1a x 1.1 ohm = ~1v.) And that is plenty of voltage to pull in that relay. And, Jim is also right. I'd sure want vacuum hooked to my distributor as the vacuum advance is there for fuel economy - and it makes a big difference. So I'd go back to DUI and tell them I want vacuum. But that's your call. Last, if I were to add the tach wire and the vacuum hose to the schematic, would that be what you'd need? Link to comment Share on other sites More sharing options...
Hstrymkrs Posted January 11, 2019 Author Share Posted January 11, 2019 William - Glad you chimed in. And, you reminded me that I need to include the tach wire. Thanks. As for the power feed, Jim is right. The white/light blue wire is powered during Start. And while it is through that resistor, my math says the voltage drop across the resistor will be ~1v. (A typical Bosch relay pulls less than an amp through the coil and with E=IR, it'll be 1a x 1.1 ohm = ~1v.) And that is plenty of voltage to pull in that relay. And, Jim is also right. I'd sure want vacuum hooked to my distributor as the vacuum advance is there for fuel economy - and it makes a big difference. So I'd go back to DUI and tell them I want vacuum. But that's your call. Last, if I were to add the tach wire and the vacuum hose to the schematic, would that be what you'd need? While looking through the fog, my initial thought is that it looks like it will work. I do not recover well from night shift so please forgive any errors I make. However, I will need to pull out my Acme Wiley Coyote work bench to find out for sure. I will call DUI back and ask them about the vacuum. It wasn't a matter of want or not want, it was a matter of it not being their currently and if I needed to route a vacuum line to the distributor. I will make the inquiry. I understand that the vacuum advance allows the engine to conserve energy so to speak when not under load. Again, I have no problem with a vacuum advance, I just wasn't sure how I would work it in and if I "needed" it. I wonder if DUI would program a better learning curve into my brain. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 11, 2019 Share Posted January 11, 2019 While looking through the fog, my initial thought is that it looks like it will work. I do not recover well from night shift so please forgive any errors I make. However, I will need to pull out my Acme Wiley Coyote work bench to find out for sure. I will call DUI back and ask them about the vacuum. It wasn't a matter of want or not want, it was a matter of it not being their currently and if I needed to route a vacuum line to the distributor. I will make the inquiry. I understand that the vacuum advance allows the engine to conserve energy so to speak when not under load. Again, I have no problem with a vacuum advance, I just wasn't sure how I would work it in and if I "needed" it. I wonder if DUI would program a better learning curve into my brain. No prob. Almost 50 years ago I worked a rotating shift and I remember not recovering from graveyards well at all. As for the vacuum, it is just a matter of running a hose, available in bulk from the parts store, to a fitting that is surely already available on the engine. For instance, you probably have HVAC controls that use vacuum. And maybe speed control. These will have manifold vacuum to them, meaning it is on all the time, and it can be used for the vacuum advance. But I like to use ported vacuum for the vacuum advance, meaning that it comes on only when the throttle is above idle. And your carb will probably have a port for that on it. So it will be really simple to hook up vacuum to the distributor, one way or the other. Concerning the learning curve, you are on the steep part of the slope. Hang in there, it is all gonna make perfect sense, soon. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted January 11, 2019 Share Posted January 11, 2019 While looking through the fog, my initial thought is that it looks like it will work. I do not recover well from night shift so please forgive any errors I make. However, I will need to pull out my Acme Wiley Coyote work bench to find out for sure. I will call DUI back and ask them about the vacuum. It wasn't a matter of want or not want, it was a matter of it not being their currently and if I needed to route a vacuum line to the distributor. I will make the inquiry. I understand that the vacuum advance allows the engine to conserve energy so to speak when not under load. Again, I have no problem with a vacuum advance, I just wasn't sure how I would work it in and if I "needed" it. I wonder if DUI would program a better learning curve into my brain. I can remember working the graveyard shift back in the '70's. Then leaving to get to high school. It's tough if it is not your regular routine. Vacuum advance allows you to factor throttle position and engine load on top of simple centrifugal advance that is determined by engine rpm, weights and springs. It allows for more advance at lower rpm while being able to control knock. If your new carb is a Holley clone it should have ports for both timed (ported) vacuum and manifold vacuum. Gary has already graciously offered to draw it all up Link to comment Share on other sites More sharing options...
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