How to Convert your OBDI Honda to Distributorless Ignition

We’ve received many requests about our original article about distributorless setup for Honda / Acura motors which allow you to ditch the stock OEM distributor and move to a completely distributorless ignition.

We’ll be showing you How to Convert your OBDI Honda and switch your distributor ignition setup to a distributor less ignition system.

Note : This conversion is for advanced users, and not recommended for the average tuner. In other words, if you have to ask why this conversion is relevant, chances are you don’t need it.

Parts needed (ex: 1992-1995 Honda civic EX)
-1 OBD I Honda
-1 AEM EMS -PN: AEM-30-1000
-1 MSD DIS 2 – PN: MSD-6211 or MSD-62111

You have many choices for Dual pole coil packs, these are the 2 setups we recommend. Setup A:
-2 MSD PN: MSD-8870
-2 GM dual pole coil packs

Setup B:
-2 Dual pole coils from an 86-91 RX-7 or Buick Grand National.

The install of the DIS system requires that you have the AEM EMS already installed and car running.

There are 2 parts to the install.
-The actual wiring and wrenching.
-The DIS and AEM Programming.

The first section we’ll go over is the Actual wiring and Wrenching.

First find a suitable location to mount the DIS System. For our install we chose the passenger side floor panel right next to the AEM.

Next we Wire in the DIS 2 to the AEM EMS.

There are 12 wires on the DIS 2 box, we will be using 10 of the 12
1- Heavy Red – Battery positive terminal.
2- Heavy Black – Battery negative terminal or engine ground.
3- small red – 12v Switched (IGN Key or Switch)
4- small red – 12v Switched (IGN Key or Switch) connects to #3 small red. This connection will be separated later and rerouted.
5- brown/orange – Coil positive
6-brown/orange – Coil positive
7- brown/white -Coil 1 negative
8- brown/green – Coil 2 negative
9- white – Ignition Input wire to trigger the coil # 1
10- green – Ignition Input wire to trigger the coil #2
11- brown- Ignition Interrupt feature. Not being used in this install.
12- Blue – 2 Step rev limit feature. Not being used in this install.

The Wiring is fairly straight forward, but there are a few little tricks we’re going to show you that make the install a Snap. All connections should be soldered and either heat shrink wrapped or electrical taped.

First disconnect the negative terminal from the battery.

We will start inside the car. Take wire #’s 9 and 10 the white and green wires on the DIS. Pull these 2 wires out of the loom leaving the others still in the loom, route the loom into the engine bay of the car, terminating next to the distributor. You may also want to route the heavy red and black wires into the engine bay at this time also The green and white wires will be soldered straight into the stock Honda ECU wiring harness, pins #A21 and # A22. Clip the wires from pins, A21 and A22, about 3.5 inches from the plugs. Now Solder the DIS white wire to pin# A21 on the ECU side of the stock Honda harness. (side that plugs into the AEM EMS). Now Solder the DIS green wire to pin#A22 of the ECU side on stock Honda harness. (side that plugs into the AEM EMS). Depending on the model of your car you may have to add a pin to #A22.

Through these 2 wires the AEM EMS tells the DIS how and when to Fire the coils.
Here’s a picture of the DIS wired into the stock Honda harness

Next take the 2 small red wires, #3 and #4 this is one of the time saver tricks.

This is the DIS harness before modified (only the red wires are shown to simplify diagram)

This is the DIS after modification. modified (only the red wires are shown to simplify diagram) Make sure you keep track of which wire is the 12v switched and which one goes to the RPM signal output.

!!Mark which wire you have for the RPM signal wire on the terminating end of the harness!!

From here we can go into the engine bay. Connect the heavy red #1 to the positive terminal of the battery (if your battery has been relocated into the trunk of the car you can use the starter positive). Connect the heavy Black #2 to the negative terminal of the battery or a good engine ground.

Next remove the distributor, taking note of its position. Next remove the distributor cap, rotor, coil and coil igniter. You should also remove the wires that go to the igniter and coil from the distributor. Once the Distributor has been stripped of the coil and igniter it should only house the sensor magnets. There are 3 of them with 2 wires each leaving only 6 wires from the distributor. (the AEM only uses 2 of the magnetic sensors but removing the unused one is more trouble than it is worth). Now the distributor is just a crank/cam position sensor. Reinstall the crank/cam position sensor. Now take the 2 wire plug, (that should already have been removed from the distributor), It has a blue wire and a black/yellow wire. Take that 2 wire plug and solder the blue wire of the plug to the red wire that was reconfigured to be the rpm signal output wire. This will give you an RPM reading directly from the DIS. Solder the Black/yellow wire to the other red wire.

!!!!!!!!!! USE EXTREME CAUTION WHEN SOLDERING THESE 2 WIRES. IMPROPER ORDER MAY CAUSE DAMAGE TO DIS. IT’S EASY TO MIX THESE 2 WIRES UP SO EXTREME CARE SHOULD TAKEN!!!!!!!!!!!

Here you can see a picture of the 2 wire plug already wired into the DIS harness, don’t forget this step in our How to Convert your OBDI Honda writeup.

Now mount the 2 coil packs. We made a custom bracket that mounts to the throttle body and the cylinder head.

You can see that the spark plug terminals have been removed from the distributor cap and a piece of aluminum riveted in place for a cleaner look. The cap is completely sealed on the inside with silicone.

Next wire in the coil packs. Take the Brown/white wire#7 and solder it to your #1 coil pack negative. Solder your coil positive to one of the 2 brown/orange wires. (There is no designated one per coil pack so use any of the 2). Solder the Brown/green wire#8 to coil pack #2 negative, and solder the other brown/orange to its positive. Connect spark plug wires of cylinders 1 and 4 to the #1 coil pack. Connect spark plug wires of cylinder 2 and 3 to the #2 coil pack. This is a waste spark setup therefore terminal designation on the coil pack is inconsequential, as long as cylinder 1 and 4 are on coil#1 and cylinder 2 and 4 are on coil #2.

Now that all the hardware is in place, time for the programming. Take the DIS box and look at the Switches on the side. There are 3 sets of them. The one on the far left is set #1 all of these should be set to off except for #4. This is the waste spark selection. If you don’t set this switch to on the car will severely stutter and misfire over 5000 RPM. Set 2 is for Staging rev limit and max speed rev limit. We didn’t use either of these features so we left all of these off. Set 3 is for speed retard timing set up and max RPM speed. Refer to DIS directions to best suit your setup. If you’re not going to use any of these features seat switches 5, 6, 7 and 8 to the on position. This gives you a 10,000 rpm rev limit.

Clean up all wiring and reconnect battery negative, now you are ready for the install part of our How to Convert your OBDI Honda article.

Now we change the options on the AEM EMS system to support the DIS System. In order to have 2 coils you have to enable the second one. Go to the options menu and select “coil”, not “coil options”. Next you want to select coil #2 and enable it, to do this you click the up arrow next to “Select coil number”, and then check the active box.

Now your second coil is active but it doesn’t know when to fire. In order to designate a firing time, go to the options menu again and go to the “coil options” menu. Now take the value of your Ign tooth# 1 and add 6 to it.

For example if you have .15 for Ign tooth #1 add 6 to it. Example (0.15 + 6 = 6.15). Now take that value and use it for your Ign tooth #2 value. You can raise the coil factor to 25 but it is not necessary. It’s possible to experiment with the dwell max teeth if you start to get inadequate spark at high RPMs but it’s shouldn’t be necessary.

Now you’re done with our How to Convert your OBDI Honda writeup! Now you can enjoy the benefits of distributorless ignition in your Honda!

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