One of the tried and true ignition boxes is the ever popular DIS-2 from MSD! This programmable ignition control box is designed for distributorless operation and delivers a high powered CD multiple spark and gives you the ability to customize a variety of rpm and timing functions.
RPM control, individual cylinder timing and 2-step are just some of the features found in this ignition box, and these parameters can be set by using a PC using MSD’s Pro-Data+ software, or with the MSD Hand Held Monitor, PN 7550.
Mounting the unit is something you have to figure out on your own. If mounted in the engine bay, keep it as far away from heat as possible. Also, think about making a sheetmetal shield to cover the unit. Here we have ours mounted behind the driver’s side strut tower, utilizing factory bolt holes that were no longer used for factory equipment.
Once you know where it’s being mounted, we can get started on the wiring. For a breakdown of DIS2 wiring, take a look at our chart below :
Power Wires – There are 2 heavy gauge wires that are responsible for getting direct battery voltage to the ignition.
Heavy Red Wire – This wire connects directly to the battery positive (+) terminal or a positive battery junction such as the starter solenoid.
Heavy Black Wire – This wire connects to a good ground, either at the battery negative (-) terminal or to the engine. Note: Engine must be grounded to battery negative.
Red Ignition Switch – This wire is responsible for turning the DIS-2 On and Off. Connect to a switched 12volt power source, such as your ignition or your turbo timer harness.
Coil 1 – Brown / Orange Wire – Positive terminal on Coil 1 Brown / White Wire – Negative Terminal on Coil 1
Coil 2 – Brown / Orange Wire – Positive terminal on Coil 2 Brown / Green Wire – Negative Terminal on Coil 2
4 pin trigger subharness
White wire – used to connect to the electronic ignition amplifier output or to the
trigger output of the ECU for coil 1.
Green Wire – used to connect to the electronic ignition amplifier output or to the
trigger output of the ECU for coil 2.
2 Pin Connector – This connector plugs into a Cam Sync Sensor to indicate when the number
one cylinder is triggered.
Gray – Tach Output – Used to determine the tach signal from rpm sensing devices, for this install you may need a tach adapter.
Purple / Blue – RPM Activation Switch. This wire will supply a ground to complete a circuit at a
desired rpm. It will handle up to 3 amps continuous.
Map Sensor – 3 Pin Connector – Brown/Violet – Brown/Yellow – Dark Brown
Used for an optional external pressure sensor for turbo or
supercharger applications. (2 – Bar/2-29 psi – PN 23121)
(3 – Bar/2-44 psi – PN 23131)
The first and easiest is the tach output. Make yourself an 8″ long wire w/ a female spade on one end. The female spade connects into the dis2 on the dipswitch side. Locate your power transistor – it’s black and directly below the plug for the coil pack, driver’s side of the intake manifold.
Next cut the wire going to the center of the coilpack. Solder the 8″ wire you made to the car-side of the cut wire. Whatever wire is left coming out of the power transistor is now just hanging in mid-air.
You’ll notice that this is the white wire pictured in the above picture. That was simple, huh? Now your tach will show rpms when the dis2 is connected, but if you install the bypass connector in the dis2 harness, and use the oem ignition, you’ll no longer have a tach output on your gauge cluster. (win some and lose some I guess)
Now the triggers. You take the factory signal, doctor it, and send it back to where it belongs. Locate the plug going to your coilpack. It should be a black, triangular plug, directly above the power transistor we just worked on. Unhook this from the coilpack, and proceed to cut the end you just unplugged about 1-1/2″ from the plug.
This is much like wiring in the Apexi Super AFC. Now you have 3 wires coming from the main loom, this is the dis2’s trigger input. The three wires are power (thick gauge), trigger 1 and trigger 2. there’s only 2 triggers because the coil for 1 and 4 fire together (at the same time) and the coil for 2 and 3 do the same.
The trigger wires are yellow w/ black stripe, and yellow w/ green stripe. Now i suggest using solder, as these connections have to pass high current/voltage thru them. Get the wiring harness included w/ your dis2. identify the trigger input wires. The white and green wires trigger the dis2 to fire(dis2 inputs). The brown/white and brown/green are the coil triggers (dis2 outputs). I chose the yellow/green wire to mate w/ the green and brown/green since there was a constant ‘green’ theme.
So from the car should be a yellow/green, which is soldered to the solid green to the dis2. Then the brown/green from the dis2 goes to the wire/connector that you previously cut off. Now do the same for the white and brown/white wire and the yellow/black factory wire. The 3rd wire is the thicker gauge factory wire used for +12 volts (the triggers are the negatives). Take the factory side and solder that to the the dis2’s specified +12 volt source. You’ll notice the red wire on the dis2 harness has an open connector on it, looks like something should plug into it; relax tho, nothing gets plugged into it.
The light blue wire is to activate the 2-step revlimit. You can get a momentary pushbutton switch from Radio Shack, and use that as your trigger for the 2-step. There are many ways of doing this simple circuit, you just have to choose how YOU want to do it.
The brown wire you won’t use unless you want to hook up a starter kill of some sort. Maybe to an already installed alarm system, or simply to a toggle switch you have in your cockpit. My ecu has the TMO security, so I just tapped this wire off so it didn’t ground by accident.
After all your wires are soldered, I suggest putting some tubing around the soldered joints. Then electrical tape over the tubing. So each soldered joint will have tubing over it, in addition to electrical tape.
Lastly, the main power for the dis2. The heavy gauge black and red wires, which come out the non-dipswitch side of the unit, are wired directly to the battery. Connect them to the battery, use of a fuse is not recommended.
Now the dipswitches:
The most important dipswitch is sw1 #4, make sure it is ON as shown in the above picture. The only other switches you will use are sw2 #4-8, and sw3 #4-8. sw2 chooses your 2 step rev-limit for stageing, burnouts, fun, etc. sw3 switches choose your high rev limit, but your factory ecu also has this.
After you setup your dip switches, you are set to go!
- Pro Street Staff