Throttle linkage coming up short (1 Viewer)

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Marietta, GA
All- looking for suggestions...

I am running a 74' FJ40 with a F1.5 and a weber 32/36 carb and stock linkage. I have been trying to get more power from the engine so after a carb rebuild and minimal change, I finally had my wife step on the gas pedal and noticed that the linkage is not opening the secondary on the carb more than 1/3 of the way.

I have adjusted the amount of travel on the pedal to linkage connector (green arrow), but am still not getting enough travel on the carb linkage (blue arrow and line). Looks like I need another 1.5 inches of travel to fully open both butterflys.

Is there an adjustment I am missing or do I need to swap out parts?

IMG_6872.jpg
 
What you are missing is something like ebay #254308042542- - -easy deal.
 
If you do go to a cable setup, hold on to your linkage for if/when you go back to OEM.
 
All- looking for suggestions...

I am running a 74' FJ40 with a F1.5 and a weber 32/36 carb and stock linkage. I have been trying to get more power from the engine

do I need to swap out parts?

Yes get rid of the under sized carb and put an oe carb on it.
 
The horizontal linkage rod has basically a 90 degree effective range of motion where the vertical rod from the pedal attaches. From 45 degrees below the horizontal to 45 degrees above. More than that and you run the risk of binding.

If the rod is tight in the carburetor anchoring bracket (nylon door pin bushing required but the range of motion required to fully throttle the carb is missing, you need to cut and extend the arm on the carburetor endso that the same range of motion at the ‘in’ end creates a greater range of motion on the ‘out’ end.

I post this because sometimes, for reasons unknown, this is an issue even with stock carburetors. It’s usually slop, but on rare occasions, linkage modification is required.
 
You might adjust where the ball attached on the throttle. Closer to the axis means more angle per distance traveled.

Personally, I would simply get a cable set-up, a 38/38, or, at least try a synchronizous conversion (available for the 32/36). The small carb needs to deliver more air.
 
Thank you guys for the info- I am upping the idle jet this weekend from a 60 to a 70 and will either lengthen the rod or change where it mounts to the throttle and report back.
 
Anything more than 1.5 on the Mix Screw is idling on the wrong circuit. That will draw vacuum to the distributor, if you are running vacuum advance, causing spark timing to be off. It also changes the fuel mix across the low range of throttle. You can get around this by drilling one or two holes (1mm) in the throttle plates opposite of the sides where the fuel mix enters the throttle bores. I'd be challenged tuning it without a readout and an O2 sensor.
 

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