So i'm ditching the fuel injection system for a triple carb setup when my motor gets back from Rebello. Its a 75 280Z. What all can I get rid of in the engine bay? I'm trying to keep as nice and clean as possible. Could I completely remove the drivers side harness? It seems to be mainly for the fuel injectors. 

 

 

-Matt

The EFI harness is essentially separate from the main harness.  It can be unplugged and disconnected without cutting any wires.  The three main connection points are at the intake manifold, at the ECU (along with the EFI relay), and at the battery.  Just start disconnecting and peeling it off until it's free.  Then you can sell the whole collection of parts to someone who's switching to EFI from carbs.

Hi Matt,

 

Better check Colorado emission laws. I'm not sure if your car is exempt. I know the guys with 77-78 cars are not. They have to pass emissions. If you are anywhere along the front range you may be required to get annual emission checks so beware. Do you qualify for "Collector Vehicle" plates? You can check DMV website to find out. Just trying to save you some grief. There is a way around this if you can register your Z on the west side of the mountains. Can't wait to see the finished product.

 

Cheers, Mike

Hi Mike, yea my car is exempt (Thankfully) The cutoff is 75

Zed Head pretty much said it. I did it with my 77 when I was in Vegas. You didn't have to pass a visual, just an emissions test which was easier than CA standards. I ran SU's on my 77 for several years and had to re-install the EFI when I moved back to CA. I removed the EFI harness and stored it away. Everything else just stayed in place ie dropping resisters, etc. And of course a lot of it went away when I removed the intake.

Have you considered the megasquirt fuel system? Been reading good things about it. Its even a good system, from what Iv'e read, as a replacement for our stock systems. Fully programmable.

And then there (is) (was) the "Hellfire" which must have disappeared into the wind?  

Ok so i'm removing my harness completely. Can I just remove the ECU as well? I noticed theres a couple relays or resistors under the dash that its connected to. I can remove these too? Thanks.

If you have a stand alone fuel pump & regulator. AND you have a stand alone ignition system (like a ZX distributor set-up) then you should be ok to remove the ECU, EFI harness, ignition module and the wires to it (in a 280z harness).

 

The 280z EFI system has interworking controls for the fuel pump so you want to make sure that the fuel pump is independent of this.  Putting a mechanical pump on the front is a way to remove all of the legacy pump headaches.

Thanks Blue!

 

Well I purchased an electric low pressure fuel pump that I was going to replace the stocker with. This wont work with the factory wiring harness near the fuel tank?

Yes it will work Haz. That is what I did with my 77 when I was running SU's when I lived in Vegas. I did pull my ECU, harness, and relays. I don't remember, not surprised, how I powered my fuel pump. I know I wired it directly to the ignition somewhere, just don't remember exactly. I did use the stock pump harness in the back. For some reason I want to say I had to pull the passenger seat to get to the pump wiring. I will think about it some more, maybe I'll remember it, and post it.

 

Oh!,

I ran a wire from the bullet connector under the passenger seat to my ignition relay. But, check your fuel pump circuit in the FSM and go from there. Not sure it's the same as mine.

Thanks! Just what I needed.

The trick to using the EFI wiring for the new pump in the back is to realize the EFI system has safety interlocks to prevent the EFI pump from running when the car is off or when the car crashed (AFM switch or oil pressure switch).  

 

The EFI relay applies power towards the pump when the car is turned on through a relay.  This power path is also gated by the crash safety interlock.

 

If you want to pull the EFI harness and components but use the wiring, you will have to do a bit of routing around these two legacy items. It is not hard to do. You  just need to understand these details it and cleverly integrate the wires for the new application.

Wow I didnt realize these cars were so high tech!