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PDXAccord79
01-28-2015, 11:59 AM
Hello everyone,

So I haven't posted on here for awhile mainly due to it being winter and me being frustrated with the car. I finally figured it out and now have the car running great and passing DEQ so I figured it's time to fix some of the horrid wiring issues with this car and add some stereo.

I already have most of it figured out but am running into problems with the distributor. I would like to swap my 79 distributor for an 81 so I can get rid of the external ICM which will eliminate some wires from the harness. My problem is I don't know how to hook it up from the coil. Does anyone have the diagram for an 81 ignition system from a Honda manual? I remember it being something nice and simple like 1 wire from the coil+ to the dizzy. Any help would be greatly appreciated.

I'm also going to swap for a 1 wire 80 amp alternator so the car doesn't feel like it's going to die with the headlights and heater on. I'll post pictures as I get it done. Hopefully everyone else is doing well!

lostforawhile
01-28-2015, 05:32 PM
Hello everyone,

So I haven't posted on here for awhile mainly due to it being winter and me being frustrated with the car. I finally figured it out and now have the car running great and passing DEQ so I figured it's time to fix some of the horrid wiring issues with this car and add some stereo.

I already have most of it figured out but am running into problems with the distributor. I would like to swap my 79 distributor for an 81 so I can get rid of the external ICM which will eliminate some wires from the harness. My problem is I don't know how to hook it up from the coil. Does anyone have the diagram for an 81 ignition system from a Honda manual? I remember it being something nice and simple like 1 wire from the coil+ to the dizzy. Any help would be greatly appreciated.

I'm also going to swap for a 1 wire 80 amp alternator so the car doesn't feel like it's going to die with the headlights and heater on. I'll post pictures as I get it done. Hopefully everyone else is doing well!

the 81 should be 1 wire from ignition switched power in, one wire out,which is switched ground, to the negative side of the coil, and the positive side of the coil is also switched from the key, the module in the dizzy should be just like the ones on carbed three geez, I know I had an ignition module from an 81 civic in my hatch for years, it was identical to the factory one in the Hitachi dizzy, the ground to the module itself is through the dizzy case, and there should be a wire grounded to the case. asfar as an alternator, why not use one from a 3g? it''s not 80 amps, but it should be plenty of current for that car. A carbed one has two wires that need power when the key is on, and it has one wire out, which is for your charge warning light, that wire will hook up to your factory wiring, and let you keep the idiot light

Hazwan
01-28-2015, 07:20 PM
the 81 should be 1 wire from ignition switched power in, one wire out,which is switched ground, to the negative side of the coil, and the positive side of the coil is also switched from the key, the module in the dizzy should be just like the ones on carbed three geez, I know I had an ignition module from an 81 civic in my hatch for years, it was identical to the factory one in the Hitachi dizzy, the ground to the module itself is through the dizzy case, and there should be a wire grounded to the case. asfar as an alternator, why not use one from a 3g? it''s not 80 amps, but it should be plenty of current for that car. A carbed one has two wires that need power when the key is on, and it has one wire out, which is for your charge warning light, that wire will hook up to your factory wiring, and let you keep the idiot light

You do realize the 3g alternator is not even close to even fit?

I have a Nissan 80A alternator for a Sentra/240sx I believe. 2ndGenGuy has one from a Sentra too. You just have to swap the pulley.

Let me find my 81 ignition diagram for you. I have it in my computer somewhere lol

lostforawhile
01-28-2015, 09:29 PM
You do realize the 3g alternator is not even close to even fit?

I have a Nissan 80A alternator for a Sentra/240sx I believe. 2ndGenGuy has one from a Sentra too. You just have to swap the pulley.

Let me find my 81 ignition diagram for you. I have it in my computer somewhere lol

I was just making a suggestion, no one ever specified it had to be a drop in, I would like to see how it all fits in there when done, I was able to put a delco internally regulated alternator on my 81 civic, it wasn't that bad, I had the same issue where the alternator didn't have enough current capability to power the accessories on the car, turn on the AC, lights, wipers, and rear defogger during a rainstorm for example, and you were draining the battery

Hazwan
01-28-2015, 10:00 PM
You said why not use a 3g alternator. And i gave you a reason why not. Sentra alternator fits without any modification to the brackets. Just swap the pulley and redo the wiring.

Why go with a more difficult option with less amperage?

PDXAccord79
01-29-2015, 07:43 AM
As far as the alternator goes I will have to modify the bracket if I don't use a Sentra/240sx. Problem is I bought an alternator from I believe a 92 Sentra and the bolt is way smaller than the bolt on the Accord. I know I can get 100+ amp alternators for the 240sx but I really need to know the year so I don't keep buying the wrong ones. Also do I need the bracket from the Nissan?

I don't think using a 3g alternator is the way to go since 80 amp 1-wire small case Chevy alternators can be found easily. If you're going to modify the bracket you might as well get an easy to replace replacement. As for the wiring most IR alternators have a BATT+ (battery), GND (ground), S (sense), and L (light). It's best to run a wire back to the battery for the sense but you can also simply jump it to BATT+ and it will work fine. This is how you make almost any 3 wire alternator a 1 wire. I'm also going to run a strap off the GND bolt to the block and chassis since that bracket is really not sufficient ground for any kind of power.

And yes the wiring diagram/ignition diagram for the 81 dizzy would be very helpful. I'm sick of that sometimes cranky external ICM and all of them I've replaced have sucked. I'm thinking the all in one dizzy is going to give me way less issues. With the external vreg and ICM out of the loop I should be able to remove a lot of wires from the front harness which is the goal. Thanks again for all the help.

Oldblueaccord
01-30-2015, 09:59 PM
Usually one wire conversion don't charge that great or at all at idle. Just be aware of that when buying since discharge at idle seems to be an issue for you.

If you do go higher amperage make sure your power out wire is sized correctly. On an old car I run one from the alt to the battery direct just to protect the old wires from over amperage.

If you up you alt pulley size it may charge better at idle. That to me might be the simplest solution unless there is a drop in upgrade.

PDXAccord79
01-31-2015, 07:23 AM
I know a Nissan alternator will for the most part drop in beyond the bottom bolt as long as I use the flat faced alternator. I know this car is going to kill the stereo when I hit the brakes with other electrical on due to that 55 amp alternator not being enough. I had the same problem on my Bug when I installed stereo and it had the same size generator. Even running directly to the battery didn't fully fix it.

I'm going to do the "big 3" upgrade for main power and have almost all parts needed right now. I'm going to run a 4ga directly from the alternator back to the battery then upgrade the main power wire to 4ga and add a 4ga wire to my stereo power distribution block. I'm also going to run a 4ga ground directly from the battery for stereo and upgrade the main ground cable to 1/0. For main power to the car I'm going to run 2 8ga to the fuse box from a distro block on the firewall and pass one through an amp meter. I'll also be replacing all the existing ground straps with 1/0 wire. I already have a yellow top in there and that does help quite a bit. The car cranks right over.

As for the pulley I found a nice calculator online so I can make sure the alternator is spinning at the right RPM during idle to generate power. Just put in RPM and pulley size and it tells you how fast they both spin. I don't think I need to change pulley size but I'll do the math just to be sure.

I'm working on a diagram for my wiring now and will post it once I'm done. This is really the last "needs to be done" upgrade on the car so I'm trying to do it right.

PDXAccord79
01-31-2015, 07:26 AM
Oh and as for charging all the alternators I'm looking at are actually 3 wire and if I need to I can run a sense wire from the battery to the alternator with little to no problems. I've heard jumping the sense to batt+ can lead to charging issues but if you run a sense wire it fixes that problem. The only other thing I need to plug in at that point is the light and that's simply patching the blue wire in from the external vreg.