Turbo EFI to 75 280Z...I'm clueless.

[EverRude]

I'm swapping an 81 Turbo motor into a 75 280z. Mechanically I have everything done. I have been writing up most of my progress here.

 

Now for the part I've been dreading.

 

Wiring.

 

Using Bumble Zee's swap thread is alot of help getting an idea of what I need to do. Especially the fact he's swapping an 81 harness as well. However his thread makes it look deceptively easy to me. Part of the reason I choose to do the swap was it looked easy...on paper. Once I get to looking at all those wires I get brain freeze.

 

The basic connections are easy. Those are all done.

 

The problem I have, aside from the fact I get lost trying to understand schematics, is finding where to hook up the wires he says to cut and splice. Where's is a good sourse of switched power in the engine bay? Constant power I assume I can get right off the battery.

 

And the fuel pump relay that is only on while cranking, running and 5 seconds of "on." How do I wire that? I assume the relay does it and just needs switched power. But his thread doesn't say that. It reads as though I have to find the right wire. The 280 relays are under the dash. The 81 ZX relay is beside the battery. I have the ZX's relay but what do I do with the relay's under the dash?

 

The ignition wiring from the coil ignitor to the EFI section. He says not to cut the yellow wire but feel free to cut the rest leaving room to work with. But looking at his pics it seems he's using most of the wiring on the coil to ignition connector line. He says what to do and draws a understandable pics of what to wire. But again. Under the dash what's a good sourse of switched power or constant power?

 

The fusible link wires he shows and says to hook to the +post on the starter. Do I need the fusible link or just hook them straight to the starter?

 

I'd rather drill out header bolts than splice wiring...

 

Please help. I'm so close to being finished.

[Daeron]

(I just got my 'net connection back after a week so I am slowly catching up on things here as I get bored with TV; I'm not sure but I think this is less recent than the discussion in your main swap thread but I'm gonna add this here)

 

You MIGHT want to get some blank pieces of paper and draw abstract diagrams of what you need to build into your car ultimately, and what each system has in it now, so that you can look at these three drawings and use them as an aide to keep the ENTIRE "big picture" in front of you while you sketch and make notes regarding the changes needed. I haven't jumped on it yet (my vehicle is a much more slow-paced project than yours, if you haven't noticed) but I'm going to alter the FSM wire diagram that I have and either use it as stock to cut pieces out of signifying my overall plan of design for certain aspects, or possibly edit out all superfluous pieces of the diagram, do som color coding, and then sketch out changes I need to make to the original diagram.

 

I would suggest possibly a hybridization of both of these ideas; Cut out the components (relay, AFM, pump, ecu, etc) from the stock wire diagrams and color code any wires that you may want.. assemble those into one coherent picture, then print that out and take it to your pile of parts and set about making reality conform to your sketch (or altering ideas to fit reality as need be) and then decide how to mount everything in the vehicle.

 

You can compare the ECU/FI relay/ component connections by comparing the two vehicle wire diagrams.. if they look largely the same then I would recommend retaining the one in the vehicle (or at least its method of installation) anywhere possible.

 

and don't hesitate to post up with things that seem almost too nit-picky or simplistic to ask advice on... in a job like this, the more brains tinker with the issues the more possibilities open up. There is no detail to fine to question.