Here are some diagrams that may be helpful to you if you are trying to install an MSD ignition on your Toyota. I have left out most wiring colors, because it varies a lot from model to model. This diagram should apply to Celicas, N/A Corollas, Trucks, anything that uses 2 pickup coils in the distributor and has the same number of cylinders as corners of the main magnetic spinning thingy on the distributor shaft (There's probably a more technical term for it). Supras work differently, 6 cylinders and about 20 points on their thingy. So this doesn't apply.

Now for a disclaimer: If it doesn't work, or you break something or hurt yourself, it's NOT MY FAULT! I'm just providing this information as entertainment about what worked on MY car. End of Disclaimer.



This is the way your car is set up now. Familiarize yourself with its operation. The 'square' and the 'pointer' rotate together on the distributor shaft. The red/white wires get 4 pulses per DISTRIBUTOR revolution (2 engine revs) and the Black/green wires get one. While starting your car, the engine spins slowly (under 400 rpm) and the red/white wires trigger the igniter to spark. In this mode there is no ecu control of spark timing.
When the car starts, the rpms increase over 400 rpm, (the ecu is monitoring engine rpm with the black/green wires) the ECU takes control of the ignition timing like this:
The red/white wires recieve a pulse,
The ignitor sends the ECU a signal on the Ne wire.
The ECU waits until the proper time, then sends a pulse to the Igniter on the IGT (ignition trigger) wire which causes the spark.
Then when the spark has fired successfully, the igniter sends the signal back to the ECU on the IGF (Ignition Feedback) wire.
When the ECU sees that the rpm is over 400, and has a valid IGF signal, it will then proceed to pulse the fuel injectors.


Follow the wires and be clear on which direction the signal is going on each wire, because if you get some wires crossed, you will not get any fuel injector pulses and the car won't run even if you still have spark.
Below is the same system with the MSD 6 btm added. The MSD 6AL is inexpensive and connects the same way. I'm using the MSD 6BTM (Boost Timing Module) Beacuse it can retard the spark as boost increases, thereby decreasing the likelyhood of detonation.
Here you see the IGF signal from the ignitor driving the white trigger wire of the MSD box (sorry it isn't labeled). The ECU still needs the IGF signal so that it will operate the injectors, so what you do is connect the TACH output of the MSD box to the ECU's IGF wire. Then when the spark has comleted sucessfully, the MSD box pulses it's tach output terminal which the ECU sees as its IGF input, then the fuel injectors fire and away we go!

It is important to notice that while using the MSD box, BOTH of the primary coil wires go to the MSD box. This is because the MSD box recharges the ignition coil with something like 900 volts so that it can recharge and spark multiple times very quickly. You can use the original Toyota coil, just make sure it is not grounded or otherwise connected to the car's electrical system. I'm using an MSD Blaster II.

While checking out the new system you will notice that instead of the single *pop* you hear from a single spark, the MSD box makes the spark sound like a *PING* instead. And the voltage is high too, it can throw an arc up to an inch, so be careful!

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