Gary Lewis Posted January 12, 2019 Share Posted January 12, 2019 The schematic above looks good and makes perfect sense for future people like myself. I will go and check out write up momentarily. I do not have C232 on my Bronco. While I haven't put hands on the actual wires, I know by looking at that schematic that I can follow it and wire up the distributor. Great job! William - That looks like C232 in the bottom of your first pic. Check that wire to see if it is yellow. All - I've done some slight tweaks on the web page, like adding links to Amazon for the relay and socket. However, now that I read about the socket I find that the load wires are 14 gauge. So I found this set of a relay and socket. But the pins on the relay aren't even tinned. Does anyone know of a good, high quality relay and socket? They don't have to be a pair. Link to comment Share on other sites More sharing options...
Steve83 Posted January 12, 2019 Share Posted January 12, 2019 ...a table which said that #14 is good for 25 amps.The one at the bottom R of this chart? https://supermotors.net/getfile/832986/thumbnail/bulbsfuseswire.jpg...the yellow circuit 37 wire should be there with an open connection available. I think it would be a 1/4" terminal but can't remember or determine whether it would be male or female.AFAIK, all '80-86 trucks have the female side of the light blue connector: https://supermotors.net/getfile/645722/thumbnail/auxbattconn.jpgDo we think it still needs its own fuse coming off the end of #37?Absolutely. Without one, a short in the wire to the DUI would NOT burn the (heavy) fusible link wire, and would probably catch fire itself....a fuse rated a little lower than the fusible link...Fusible links aren't actually rated for current. They're engineered into the harness to protect the other wire. So the fuse should be sized for the DUI system's designed peak current. If it says it draws a maximum of 5A, use a 5A fuse. A fuse doesn't blow until current is 111-125% of its rating. https://supermotors.net/getfile/849725/thumbnail/fusesblades.jpgI do not have C232 on my Bronco. It's sometimes taped up in the harness, or farther down under the booster. Look at my photo above. Link to comment Share on other sites More sharing options...
Hstrymkrs Posted January 12, 2019 Author Share Posted January 12, 2019 William - That looks like C232 in the bottom of your first pic. Check that wire to see if it is yellow. All - I've done some slight tweaks on the web page, like adding links to Amazon for the relay and socket. However, now that I read about the socket I find that the load wires are 14 gauge. So I found this set of a relay and socket. But the pins on the relay aren't even tinned. Does anyone know of a good, high quality relay and socket? They don't have to be a pair. It is a green/yellow color. I will need to put a meter on it when there is power. It just comes out of the wiring harness that exits the firewall. I will explore it further when there is daylight. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 12, 2019 Share Posted January 12, 2019 ...a table which said that #14 is good for 25 amps.The one at the bottom R of this chart? https://supermotors.net/getfile/832986/thumbnail/bulbsfuseswire.jpg...the yellow circuit 37 wire should be there with an open connection available. I think it would be a 1/4" terminal but can't remember or determine whether it would be male or female.AFAIK, all '80-86 trucks have the female side of the light blue connector: https://supermotors.net/getfile/645722/thumbnail/auxbattconn.jpgDo we think it still needs its own fuse coming off the end of #37?Absolutely. Without one, a short in the wire to the DUI would NOT burn the (heavy) fusible link wire, and would probably catch fire itself....a fuse rated a little lower than the fusible link...Fusible links aren't actually rated for current. They're engineered into the harness to protect the other wire. So the fuse should be sized for the DUI system's designed peak current. If it says it draws a maximum of 5A, use a 5A fuse. A fuse doesn't blow until current is 111-125% of its rating. https://supermotors.net/getfile/849725/thumbnail/fusesblades.jpgI do not have C232 on my Bronco. It's sometimes taped up in the harness, or farther down under the booster. Look at my photo above. Steve - Your chart doesn't quite look like the one I saw earlier today. Mine is simpler, if I remember correctly. But it could be the same one. We will see next week. As for that circuit, I agree. I think all the trucks have that circuit, just not the relay or stud unless they had the aux bat or trailer. Oh, or DRW. But, there were two different sized fuseble links feeding them, depending on whether you have an ammeter or not. That bit I don't really understand though. And, the fuse is in the drawing now. But I wouldn't put a 5A fuse in for HEI. The inrush current is apparently quite heavy, and if you use #12 wire I'd go for 20A since the wire can easily handle that much. Link to comment Share on other sites More sharing options...
Steve83 Posted January 12, 2019 Share Posted January 12, 2019 That bit I don't really understand though.It might just be an indicator of the real reason behind the difference. Possibly, the alternator output dictated the use of an ammeter or light; so the presence of the meter would indicate the fusible link size, without being the direct cause for it.I wouldn't put a 5A fuse in for HEI.That was just an example.I'd go for 20A since the wire can easily handle that much.What the wire can handle isn't relevant - the fuse should be sized for what the load requires, which should be shown in the system's manual. I'd only use a 20A fuse if that's what this particular system needs. If loads are added later, they can either get their own fuses, or the single fuse can be replaced with one sized for the combined loads. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 12, 2019 Share Posted January 12, 2019 That bit I don't really understand though.It might just be an indicator of the real reason behind the difference. Possibly, the alternator output dictated the use of an ammeter or light; so the presence of the meter would indicate the fusible link size, without being the direct cause for it.I wouldn't put a 5A fuse in for HEI.That was just an example.I'd go for 20A since the wire can easily handle that much.What the wire can handle isn't relevant - the fuse should be sized for what the load requires, which should be shown in the system's manual. I'd only use a 20A fuse if that's what this particular system needs. If loads are added later, they can either get their own fuses, or the single fuse can be replaced with one sized for the combined loads. Yes, the alternator size may be part of the answer to why the different fuselinks. Something I've not looked for in the documentation is if idiot lights required the base 40A alternator. I would have thought I'd see that, but haven't specifically looked for it. But, that would play into the fuselink difference. And, speaking of what I can't find, I can't find a recommended fuse size from DUI. Perhaps it is there, but I've read the installation instructions several times and I do not see a recommended fuse size nor the current draw. And the lack of that info is why I suggested a 20A fuse. However, a better approach would be to call them and ask. What I did find is that the distributor needs at least 10.5 volts to work. So, with that info and the fact that they recommend #12 wire, the dizzy must be a very low-impedance device and pull lots of current. So I'd fuse big to ensure the fuse isn't running hot and fails when you hit a bump way off the beaten path. I agree that's not the scientific way to choose fuse sizes, but all you are jeopardizing in this case is the distributor's electronics should it short internally. And if it shorts internally it is gone anyway. Link to comment Share on other sites More sharing options...
Steve83 Posted January 12, 2019 Share Posted January 12, 2019 ...all you are jeopardizing in this case is the distributor's electronics should it short internally.A fuse isn't to protect the devices that use it; it's to protect the WIRES between the fuse & devices from overheating or setting their insulation on fire. In case the device fails internally, or the wiring harness shorts. So putting in an oversize fuse still isn't the way to go; but as long as it's not so big that the wire can overheat with that much current, it's relatively safe. If the mfr. doesn't specify the peak current draw (which is surprising to me), it can be either calculated, or guesstimated by measurement. Measure the resistance through each current-consuming component (coil & ignition module in this case), and use Ohm's law (i = V/r, where V is peak voltage; i.e. 15.5) to calculate peak current. Or measure current with a DMM when it's working normally, and multiply by ~1.1 (to give it 10% extra) to get an expected peak. Starting off with a too-small fuse is safer than too-large; if the fuse blows rapidly, go 1 size larger. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted January 12, 2019 Share Posted January 12, 2019 Starting off with a too-small fuse is safer than too-large; if the fuse blows rapidly, go 1 size larger. Yeah, I don't know how much I like the idea of losing my ignition while out on public roads... Bad enough when my DSII box decides to crap out. If none of the rest of the harness is going to get hurt, I'm going to fuse it for the rating of the relay (30/40A) Â Link to comment Share on other sites More sharing options...
NotEnoughTrucks Posted January 13, 2019 Share Posted January 13, 2019 Of course I am really late to the party here, but the discussion reminds me of something our friend Dan Stern, of Daniel Stern Lighting fame posted up on Mopar forums years ago. He is also well known as SlantsixDan. For what it's worth, here is the discussion from slantsix.org . http://www.slantsix.org/forum/viewtopic.php?t=15779 I did a little playing around with HEI modules years back and I was able to trigger them with a Ford DSII distributor. Never did try running an engine with one, but I don't see why not? Link to comment Share on other sites More sharing options...
85lebaront2 Posted January 13, 2019 Share Posted January 13, 2019 Of course I am really late to the party here, but the discussion reminds me of something our friend Dan Stern, of Daniel Stern Lighting fame posted up on Mopar forums years ago. He is also well known as SlantsixDan. For what it's worth, here is the discussion from slantsix.org . http://www.slantsix.org/forum/viewtopic.php?t=15779 I did a little playing around with HEI modules years back and I was able to trigger them with a Ford DSII distributor. Never did try running an engine with one, but I don't see why not? Essentially, what you show is what Lucas did for their "Constant Energy" ignition, the only difference was they kept the original coil from the Opus system as it was apparently compatible. Their pickup looked like Chrysler electronic ignition pickup and used a similar close gap. I am quite confident that a Ford DS-II pickup would trigger it nicely, and if you retain the three lead plug, black is ground. This is why a DS-II system works even mounted on a plastic inner fender. Link to comment Share on other sites More sharing options...
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