Hello all. So I have an AE86 that I'm putting a stock S5 in. I have read the fc3spro write up, but because I do not have a body harness I am still in the dark on how to wire my msd 6a's. The question I have is how do I wire the 2 msd 6a's to my ecu or cas? Do I need the factory ignotors? Can I use a distributor instead of the cas? Please halp!

 

you need to find the ECU ignition trigger wire from the ECU and wire that up to fire the MSD, remove the ignitors from the FC coil and wire the MSD directly to the coils themselves.

there is 3 ignition trigger wires from the ECU, a single one to fire the leadings and 2 for the trailings to fire each trailing coil induvidually. the leading is waste spark so both coils fire at the same time.

not sure about 2 MSD boxes, you should need 3 to do them all.

leading trigger circuit= pin 1H at ECU
trailing ignition circuits= pin 1G and 1J at ECU

for the most part it's best to just wire up a single MSD to fire the leadings, firing the trailings is a waste money for an upgrade.

 

Thank you. I though there would have to be a way, lol. I forgot to mention that It has s4 electronics with an s4 ecu. Does anyone have the ignition pin out for a N/A S4 ecu? I have two msd boxes that i would like to run to both of the stock coils.

 

Like rotaryevolution mentioned, you can't really run two. You either run one on the leading, or run another two (one on each trailing) for a total of three.

Here is the write up:
FC3S Pro v2.0:&nbsp HOW-TO - CDI (MSD/Crane) Installation

 

Thank you for the fast replies. I'll just be running one.

 

pins X, U and V on the series 4 are for the ignition circuits. had an issue taking a SS of the page so i couldn't get the pinout put up.