I know this is probably out there already but does anyone have any pictures of their carb setups so I can get a better understanding of how to set them up. Fuel line,fuel return line, throttle cable, and what all these hoses and that are on it for. I have a carbed 1983 280ZX with a naturally aspirated N54 any help would be appreciated.

 

 

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https://www.google.com/search?client=ms-android-americamovil-us-revc&source=android-home&source=hp&ei=MOalXeK-IIec_Qacxq-gBA&q=240z+su+carb+diagram+&oq=240z+su+carb+diagram+&gs_l=mobile-gws-wiz-hp.3..33i22i29i30.5004.17168..18230...0.0..0.159.2435.3j17......0....1.......8..41j41i299j41i10j41i13i275j41i10i299j0j46j0i131j0i22i30j33i299j33i160.P2aVneooU_0

Click on that google search. A lot of stuff on the SUs.

Post some photos of your intake and we can annotate them to help you

Post some photos of your intake and we can annotate them to help you

Ok so this is what I’d like to put on I have it here. Do I need to hook up vacuum lines?


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The only vacuum line needed is the one that provides vacuum to the brake booster.   You have a 1973 or 74 manifold so you can remove most parts on it and ensure that all holes are plugged.

No need to plug water holes.

You will need a way to hook up the throttle return springs.

You will also need a low pressure fuel source ~3 to 4psi.

 

Here is a minimalist application of SU's on an L28

For running the fuel lines, you could use -6AN braided lines. When I first swapped in an L28 with the N47 Maxima head, I changed over to braided lines because I was only running an electric fuel pump. (The head had not been opened up for a mechanical fuel pump.) I was using a Holley Blue fuel pump and ran it to a Holley fuel pressure regulator in the engine bay. I didn't need to run a return since the fuel pump is internally bypassed, but you could run the return from the FPR. I installed a fitting for a fuel pressure gauge and dead-headed the fuel rails for the carburetors. You can even get banjo fittings for the SU carburetors so you can run braided line all the way to the carburetors if you want.

Here is a link to a photo of the carburetors before I converted everything to fuel injection. https://photos.app.goo.gl/Fd1QoAfuZaBqGoKZA

Actually, if you want to drop some coin, the Patton Machine fuel injection kit would be a nice way to go on your setup.

The only vacuum line needed is the one that provides vacuum to the brake booster.   You have a 1973 or 74 manifold so you can remove most parts on it and ensure that all holes are plugged.
No need to plug water holes.
You will need a way to hook up the throttle return springs.
You will also need a low pressure fuel source ~3 to 4psi.
 
Here is a minimalist application of SU's on an L28

Ok thanks that will really help! However where could I find the rods for the throttle? And why such a low pressure?


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13 minutes ago, toastedboy54 said:

 

Ok thanks that will really help! However where could I find the rods for the throttle? And why such a low pressure?


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Linkage: https://zcarsource.com/catalogsearch/result/?q=linkage

If you run higher fuel pressure, the fuel will push the floats down, and you will get too much fuel in the fuel bowls. That's a bad thing.

Linkage: https://zcarsource.com/catalogsearch/result/?q=linkage
If you run higher fuel pressure, the fuel will push the floats down, and you will get too much fuel in the fuel bowls. That's a bad thing.

How hard do you think it would be to just run a four barrel? I am kinda tapped for cash so it will be a whole before I can get linkage and I’m already setup for the four barrel.


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With the 4 barrel carburetors, the challenge is to balance out being too lean on 1 & 6 with being too rich on 3 & 4. I've never messed with a 4 barrel myself. You still need about the same low fuel pressure for the 4 barrel carburetor as you do the SUs.

The 4 barrel dooesn't feed fuel as evenly. You will have to buy it and the manifold, which won't be cheaper than just making your SU's work and the 4 barrel will be harder to adjust the mixture versus the very simple SU's