hey guys,
am trying to figure out what the black wire with female bullet connector is used for on the leading coil. am going to be using it on my FB so need to make the corresponding wiring harness on the car. couldn't find anything in the wiring diagram myself. thanks for the help.

 

leave it alone, it is a plugin for the factory tool RPM test lead.

the 2 pin connector is the only one you need to worry about, if you are needing the ignitor inside the coil that is.

 

Thanks. Finally found the same answer here: https://www.rx7club.com/2nd-generati...iring-1091166/

 

Rotaryevolution...just to make sure, the coils/igniters are grounded simply by them being bolted to the car, is that correct? I've made a bracket to mount them in my car so if that is right, I'll need to remove it and make sure I have good contact. tia

 

yes it is, you could also run a ground strap if it is isolated.

 

If you don't have a factory rpm tool to check that pin, you can use an automotive multimeter. Harbor freight has some for 20 bucks or so (although no one there will have any idea what you are talking about). You can adjust your idle to dead on with it using that pin.

 

if you use that pin for a hertz signal just be sure you have a meter on the appropriate setting or you will fry the ignitor and brick the coil.

 

does the FC RPM signal come from the coil/igniter like the FB? am trying to figure out how to do the tach on the FB...this is for the REW swap but the FD gets its signal from the ECU but not sure if they are the same.

 

the tach signal comes from the brown wire off the FC trailing coil iirc. i don't recall which color wire that is on the actual coil side since they change colors after that point. you could get the tach signal from that bullet connector on the leading coil but IMO you don't want to lose that coil, so i would avoid it if you can.