FI TO SU CARB CONVERSION

[Acarrier]

Hi, I’m rebuilding a 1978 280z. I want to swap it to SU dual carbs. Does anyone know of used carbs and all of the other required stuff? Or where I can find them? I can rebuild the carbs if they are in need. Thanks, Andrew 

[Patcon]

Ebay for rebuildables but if you source them from Ztherapy they will be correct right out of the box. Might want to find some cores though

[SteveJ]

So why do you want to go backwards to SUs from the fuel injection?

[240260280]

I just did it on a 77:

1. Get a 3 to 4 psi electric pump or install a mechanical pump on the head. Remove the high pressure EFI pump (you can use it but stepping the pressure from 50psi to 3psi is risky if it fails... you can open the return line orifice to reduce pressure in the system .  If you install a low pressure electric pump, you can re-use the EFI pump wiring if you deal with the EFI fuel shut-off and EFI relays, I just installed a 4psi pump and wired it up in the engine bay. I did not re-use the EFI pump wiring.

2. Remove the EFI harness and EFI contraptions.

4. Get a manifold gasket that has the bolt holes for the carb manifold.

5. Plumb in Fuel Pressure Regulator (I used a Redline Weber regulator).

6. Plumb in a fuel filter (remove the high pressure one).

7. Relocate the mount for the shepherd's hook linkage  (on firewall) and adjust the linkage as needed.

8. Install new manifold gasket and carbs.

Edited July 16, 2018 by 240260280

[siteunseen]

Good thread to read.

 

[madkaw]

It’s definitely easier going EFI to carbs then the other way around