REWIRING YOUR IGNITION COIL

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 immediately noticed a smoother drive, smoother boost transition, 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.

What you will need:

• At least four feet of 12gauge wire depending on where you get 12v from.
• A relay. 30amp seems to work well
• A 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.....

1. Disconnect battery positive and negative.
2. 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.
3. Make sure the connection is solid. I would advise not using a crimper. If you do, solder it on.
4. 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.
5. Cut the positive wire running to your coil and solder it to terminal 86 or 85. Either will work
6. 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.
7. 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.
8. Re-connect positive and negative battery cables.
9. 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:
The red wire coming from between my PSR is my 12v common.

Click on picture to enlarge.

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.

Click on picture to enlarge.

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.

Click on picture to enlarge.

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