Ignition mod I have been trying out(For external coil)

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nissanfanatic
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Well I got a lil creative a few weeks ago. I went ahead and tested the positive terminal of the coil with ignition on and found it to be 11.7 Volts constant. The ECU grounds the coil to fire it and to adjust timing, it grounds at different times.

So what I did is very similar to the fuel pump hotwiring mod. I took a 30a relay, some 12g wire, a fuse, and a couple crimps and hotwired the positive terminal of the coil. I ran a 12g lead from my 4g battery cable to the relay. I then ran 12g from the relay to the positive side of the coil. Next, I used the stock coil wire to switch the relay on and off and just grounded to chassis.

I immediatly noticed a smoother drive, smoother boost transistion, and smoother WOT pull. Starting is much snappier now. I just figured I would share this with you all. I have been running it for prolly three weeks now. Ran at the track once and I have been running the hell out of the car too. It works. I also had slight misfiring in boost after switching to colder plugs that disappeared after wiring the coil. So, take this for what you will. Enjoy.


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Jookmasta
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u shouldve mentioned this to me while i was up there man! lol. so u basically used 12 gauge wire on the positive side of the coil? and u wired the positive directly from the battery as supposed to using the positive from the coil wire plug? also u grounded the relay to the chassis and still used the negative wire from the coil plug then? or was that wire also upgraded?

nissanfanatic
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Yes. The positive coil wire is now the trigger for the relay. And you run 12g from the battery to the relay common terminal. You then run 12g wire from the relay to the positive coil terminal.

Yes you still use the stock ground wire. Don't mess with that wire at all when doing this mod.

Just put the relay ground to a chassis bolt.

I believe I did mention it to you.

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Jookmasta
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so then the positive coil plug wire and the new 12 gauge wire from the battery sit on the positive side of the relay?

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WDRacing
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Cory, you've sparked my interest. Shoot me some pics would ya? Or post them up on here. Increasing the voltage is a great way to add spark.

WD

scheffler
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dito post up pics

neoamd
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pics and a how to would be scweet!

nissanfanatic
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No digi cam...

And I tried drawing a pic in paint, but for some reason, the photopost pic hosting won't host bitmap images.... I can send them on aim tho...

aim=nissanfanatic240

nissanfanatic
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What you will need:

At least four feet of 12gauge wire depending on where you get 12v from.A relay. 30amp seems to work wellA fuse. This varies on the size of the wire you use. For 12g, use a 20 or 30amp.A Crimp for use with your coil positive.

Okay, on the relay.

Get a standard 30a relay and:

pin 30-Common. This is where you will run 12g from the battery too.pin 87-This is where you will run 12g wire from the relay to the positive terminal on the coil.pin 86-Either trigger or ground. Trigger is the stock coil positive wire.pin 85-Either trigger or ground. Trigger is the stock coil positive wire.

On pin 85 and 86, polarity does not matter.

Note: I cannot stress enough the importance of a good electrical connection. Therefore, SOLDER ALL CONNECTIONS! I even went as far as to solder the wire directly to the relay pin.

So.....

Step one: Disconnect battery positive and negative.Step two: Find a good source to get a sold 12v from. Remember the reason you are doing this mod and don't get it from a light or something.lolStep three: Make sure the connection is solid. I would advise not using a crimper. If you do, solder it on.Step four: Now run the wire wherever you like to the coil. Keep it clear of the exhuast, turbo, and fan. All of which will eat your wire. Connect this wire to terminal 30 on your relay. Put the fuse somewhere on this wire.Step five: Cut the positive wire running to your coil and solder it to terminal 86 or 85. Either will workStep six: Solder 12g wire to terminal 85 or 86 depending on which you used for trigger, use the free terminal. And run this wire to ground.Step seven: Now run a piece of 12g wire from terminal 87 to the coil positive terminal. You will prolly end up using a crimp connector, but solder it on.Step eight: Re-connect positive and negative battery cables.Step nine: See how it runs.

To take full advantage of this mod, replace your stock coil with a higher power coil. I use a MSD Blaster SS coil.

Here are some pics: (Click to enlarge, 56k safe)The red wire coming from between my PSR is my 12v common.This shows how each terminal is set up and shows where my stock positive coil wire goes. Note it isn't the same color as yours. I had done so much splicing on it that I ended up having to solder a new piece on.This is to show you where I am getting my 12v source from. You can see the red wire runs behind the engine and between the power steering pump resovoir to the relay.This is the result:

Will net better results for larger budgets.
Modified by nissanfanatic at 6:08 PM 7/21/2005

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klattr1
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awesome post contribution!

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fiznat
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^^ agreed. I'll add it to the stickied threads list. If anyone can do this and get pics that would be awesome!

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WDRacing
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Cory, email them to me, I'll edit them and post them for you.

[email protected]

nissanfanatic
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Pics are up. 56k safe. Had to bum a camera off my boss.lol

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Import_Ant
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on this note I added a supplimentary ground wire to my alternator. I'm seeing over a volt increase according to my Apexi Auto-timer. that stock ground there is PUNY!

just need 3 feet of 10 or 8 gauge wire, ring terminals, and an 8mm socket.

I ran the ground to my negative battery terminal. same on my brother's 240. noticed smoother idle as a result.

thekawaii
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Ok. let me make sure i know what i'm doing

so. The Orange top wire goes to pin 87. And black box at the bottom goes to pin 85, It's a trigger.

right?

And i don't know where to get the 'good 12v' source..... can i just connect it directly from the battery? yes? no?


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Jookmasta
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yes the good source can come directly off the battery..........i have it run this way.

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4felix20
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very cool.

now i just need to find a write up for converting the ignition/ distributor on a S14 to S13.

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Edub1
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My battery light always comes on when the North Stars are on. My alternator is less than a year old. I wonder if it's the alternator wires.

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hakosuka86
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Hmm very nice I will try it. thanx

ka-t 300
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are you still running that big to4r ? and can you run this ignition set up on s-14s 96

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sunnys14
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will this mod work for s14 internal coil also?

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neverlift
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this is a 2 1/2 y/o post folks.....

anywho yes it should work for the s14, but to take full advantage get an external coil, a 30 canister from msd will work fine. I have it done to my 4.3 vortech, probably picked up a 1 or 2 to the gallon, idle went down to 650 without any hunting.... honestly this is the best bang for you buck mod hands down, I've owned a msd box, it died, but after its install in my old truck(another 4.3 vortec) and noticing little from a performance stand point, this is better. An msd box is overkill for 90% of the kat guys. HOWEVER I might try summits new digital box w/ built in revlimiter for 159

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Jookmasta
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did this mod 2 years ago when it came out..........no issues what so ever. car did feel a bit stronger after the mod. it got my approval way back when lol.

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sunnys14
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so i can splice the + wire going into the distributor and run it to a relay just like a s13?

there seems to be 2 wires going into the dizzy, a green with black stripe and black with red stripe, which one is the +?

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PantherRacer
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sunnys14 wrote:so i can splice the + wire going into the distributor and run it to a relay just like a s13?

there seems to be 2 wires going into the dizzy, a green with black stripe and black with red stripe, which one is the +?
yea, can I please get some more clarity on if it's the same for the S14?

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driftin_sr20det
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good question!

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neverlift
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i dont recall off top of my head but IIRC the green/black is positive, take a look in the fsm(or a volt meter, one will be constant and the other pulse) for your car, you want the positive to split and feed your relay 12volts...

in theory this should work with ANY coil and ANY make/model with a coil. I've used stocksohc/dohc canisters of various brands and an msd blaster ss coil. I even did it to my wifes jimmy idle was very much smoothed on that thing, also gained about a mile per gallon

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gingerbredman
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oh yay fun!! i think im gonna do this today. it should balance the voltage im losing from having my electric fans full blast all the time lol oh btw i only have the stock coil, ya think it's safe?

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gingerbredman
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reckon i can't do it on a stock coil..seeing as there's 3 frickin harnesses connected to it.

adamtsiw
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Good tech write up, this will be what my weekend will consist of


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