Dumb question: What is this and do I need it?

[bschiltz]

Hi guys,

I'm swaping in a carb'd 86 305 into a 1979 280zx. I've refered to the JTR wiring, searched on here and followed the schematics in my Chilton's guide, but I'm still not realy sure what these are? I think they are part of the FI system?

 

The black box and brass cased resistor like things:

 

The black box here:

 

Do I need these or do I just use the wires (ignition) that go into them to wire into the chevy motor?

 

Thanks

Ben

[jimszx]

The rear box contains your Fuseble links, I left them in on my 79zx they are just like oversized fuses. The front box contains relays for different systems. The choice is yours depending on the systems you are keeping.

 

 

Jim

[that240guy]

I chucked absolutely everything and only used 2 wires from inside the car. I used a wiring diagram and test line to find the wire that turns on the ignition and the wire that gives juice to the starter solenoid when you crank. Thats it. THe only other wires that need to be connected are all the white wires with red stripes need B+ power. That's it!

[VinhZXT]

I see you still have the EFI wiring there. You can remove the EFI wiring from the small black box to the computer. You can remove the fusible links but you have to replace them with Maxi fuses. Otherwise you won't have any short circuit protection.

 

The big black box in the front you can cut it if and only if you don't plan to use the head lights and horn. The headlights and horn relays are in that big black box. GL

Vinh

[Paz8]

I did an 83' and left the relay box and fuse links as is, I would NOT suggest removing them unless your VERY good at wiring things from scratch. As mentioned the relay box controls the headlights, parking lights, A/C, bulb check, and neutral start if an auto trans. The fuse links will stop your wiring from melt down if something goes wrong. This stuff does NOT need to be removed for your engine swap.

[bschiltz]

Thanks guys. One last question... in the top pic. there is a bundle of wires that goes into the hole just behind the black box(usually covered with a black plate) , but I haven't been able to follow them. Any ideas where these go?

 

Thanks again

Ben

[Paz8]

Two relays in that fender hole, the small metal one is the horn relay, the other relay was the EFI relay to power the computer when the ign. key is on or crank, I kept the relays and used the red wire from the EFI relay to power up my electric choke on the carb (solid red wire). There is also a large wire connector plug in that hole that goes into the interior of of car, don't mess with it you'll need it as is. Wouldn't hurt to spray all the connectors with electrical cleaner, mine were a little corroded.

[bschiltz]

When you say the large wire plug are you talking about #2 in the pic below? Two of the green wires go into the EFI harness and one goes to the relay, then into the into the harness.

 

Also, which red wire is used for the electric choke? Is it the one that comes out of the ignition box at #4? There's a blue and red wire that come out of the box (#3), then the blue goes to the EFI relay (#1) and the red wire turns into the yellow wire that goes into the relay (in pic two). There's also a red wire, white/red, white/black, and two heavy gauge white wires that form a harness that goes into the fender hole.

[Forces]

I chucked absolutely everything and only used 2 wires from inside the car. I used a wiring diagram and test line to find the wire that turns on the ignition and the wire that gives juice to the starter solenoid when you crank. Thats it. THe only other wires that need to be connected are all the white wires with red stripes need B+ power. That's it!

 

 

Thats almost exactly what I did. The only difference on mine is that I have a single post starter, so I used a Ford starter relay.

*EDIT*

But I mine isn't a ZX, its a 76' 280Z

[Paz8]

There is a large connector in that fender opening, shine a light in there and you will see it, it powers everything inside the car and operates the horn, headlights,parking lights, turn signals, etc., leave it alone. I can't tell from your pics, but the solid red wire I used was in the harness that runs across the top of the firewall and goes to the driver side fender, I also used the Blue/ red wire in the same harness to pull in the existing fuel pump relay. Like I said my ZX is an 83 the wiring may be different on yours, I not sure. The only advise I can give you is that there is a lot more wiring in a ZX than a Z, don't just cut everything and worry later. I have 30 years working with electronics and it no big deal for me but if you have to pay someone to figure out were everything goes it will cost ya big time.

[bschiltz]

Alright guys, thanks. I think I'll be able to get everything sorted.