Wiring the MSD Ignition System
Our Infinitybox systems are used to power all of the electrical functions in your car. This includes all of the systems that run your engine. One of the most popular ignition systems in the automotive restoration and performance space is from MSD. The MSD 6AL is a powerful and easy to install Ignition Control system. It gets the spark to the engine but our Infinitybox system gets it the power it needs to run. This blog post shows how easy it is to wire on your key-on or ignition power to the MSD 6AL. This instructions will work for any of the Ignition Control systems in the MSD lineup.
Before you get too far, it is very important that you read and follow the instructions that come with your ignition system. We are going to show you how to wire the key-on power. You need to refer to their instructions and diagrams to wire all of the other connections that go to their box. Their manual highlights warnings and critical things to follow when you are wiring their boxes. Be sure to read these and completely understand them before you proceed. You can download a copy of the MSD manual by clicking on this link.
Also, this blog post and wiring diagram show you only how to wire the key-on power to the ignition system. See the manual that came with your Infinitybox harness kit and other wiring diagrams for the rest of the functions in the car.
This picture shows you a simple diagram for wiring the MSD 6AL.
There are three wires from the MSD 6AL that we will consider for this wiring diagram. The heavy red wire, the heavy black wire and the smaller red wire.
- Heavy Red (Positive)- This wire connects directly to the battery positive (+) terminal or to a positive battery junction or the positive side of the starter solenoid. Note: Never connect this to the alternator.
- Heavy Black (Negative)- This wire connects to a good ground, either at the battery negative (-) terminal or to the engine. We can’t stress enough the importance of good ground connections. Spend some time here and do this right.
- Red- This wire connects to the POWERCELL ignition output on the Infinitybox system. See your configuration sheet for the location and color of this wire.
- Connect the remaining wires according to the MSD instruction manual.
The heavy red wire that brings the primary power from the battery is fused internally to the MSD 6AL but this does not protect the wire if it were to get shorted to ground. We recommend putting a fuse ahead of this wire at the point where you connect it to the battery. A 25-amp fuse in this wire would safely protect it.
You are then going to connect the MASTERCELL input for ignition to your ignition switch. The input works by simply being connected to ground. See the configuration sheet that came with your kit for the connector location and wire color for the ignition input. You can also choose to use our integrated one-button start input to control both the ignition and the starter. Again, see your configuration sheet for the location and color of this wire.
The POWERCELL ignition output is your key-on power. You are going to connect this to the red wire on the MSD. You can also use this wire to power other accessories in the car that need ignition power. Examples include gauge power, ignition power for a head-unit and ignition power for a Vintage Air system. You can create a simple ignition power bus using a terminal strip for all of these functions. You can use the Infinitybox Splice Saver Kit to create a reliable buss bar.
You need to insert a fuse into the POWERCELL to protect the ignition harness. Remember that a fuse is designed to protect the wiring in the harness. The fuse should be sized to protect the smallest gauge of wire in the harness connected to that output. All of our standard harnesses are 14-AWG wire, so you can protect them with a 25-amp fuse. If you connect any smaller wires to these outputs, you need to choose the right size fuse to protect the wire. See other posts in our blog about proper selection of fuses for different wire gauges.
You can download a PDF of this wiring diagram by clicking this link.
If you have any questions about this wiring diagram or anything else with our Infinitybox system, give our technical support team a call. We can be reached at (847) 232-1991 or email@example.com. You can contact our team directly by clicking this link.