Seems weird that the throttle cable would pull toward the front of the car, like the TV cable does. Can you post a photo of the carburetor and linkage?
I'm confused, throttle pulls cable (or rod) in, whereas TV cable is pulled out. Not understanding how they can both work same direction? Sent from my SM-A102U using The H.A.M.B. mobile app
My carbs are apparently made to be pushed open, rather than pulled. I wasn’t expecting that until I got this far so now I’m trying to figure out how to make everything work together. I’m thinking a bellcrank and solid rod to push the throttle open.
Could you connect to the linkage that moves forward? I'd like to see a pic of the accelerator pedal set up.
I've hooked up one in my personal car a couple years back with a turbo 350 to the throttle pedal through the firewall worked out good
However you do it, you need to get the geometry right. The TV cable has to move the same distance as the throttle cable or rods do.
I must be missing something. Hook the throttle linkage up to the lower connection on the middle carb arm. Pull it back and the progressive linkage works.
Help me understand your throttle setup - I’m not familiar with it and it doesn’t make sense to me. The throttle shafts in your picture turn counterclockwise to open? And the ‘front’ is to the left? In trade, I offer this link about TV cable dynamics (though you haven’t said which trans you have ). http://purplesagetradingpost.com/sumner/techinfo/700R4p7.html John
Ok, I see now. Holley 94s, but your linkage doesn’t look like it is adjusted right (I don’t have those carbs though). Here is a pic from elsewhere on the HAMB showing another setup that appears correct. Perhaps you can attach your TV cable to the upper part of the center arm of the progressive linkage so it is pulled with the throttle arm. John
While the center carb arm is less common than some, there is nothing wrong with his linkage. It function just as the other one posted. I would rotate all of the carb arms clockwise so that they are about 1 o'clock, or slightly less, with the carbs closed. The top holes on the center carb arm, along with the adjustable stops, are for adjusting the timing of the tip in point for the secondary carbs. The throttle linkage attaches to the bottom of the center arm.
Thank you Jim, I believe you have solved my problem. So the bottom of the center arm would give enough throw for the throttle? I haven’t tried to adjust anything yet, just stuck the linkage on there to see what I had. Your explanation sure would simplify things.
The center carb arm from mounting hole to the end hole appears to be the same as the two outer carb arms. And about what you see most often on multi carb setups. So should have plenty of leverage with an average pedal linkage. Your linkage differs from most in that your center carb arm has a larger range of adjustment for tipping in the secondary carbs. Looks like you could adjust it to get full opening on the center carb and never tip in the secondary carbs if you wanted to do so. The three top holes in the center carb arm gives you three different arcs to control amount and rate of travel on the secondary carbs. You also use the slide adjustment as part of the setup. The tuning of multi carbs is not a "set it and forget it" proposition. You should be able to get the linkage adjusted and test the carb opening positions right now. You want a 85% solution before you ever try to start it up. When actually starting it up, just have the center carb hooked to any linkage so you can set the idle speed and test how tight, or not, the end carbs seal. Save yourself a bunch of time and buy a UniSync. Looks like you have idle circuits in the end carbs should you need to balance things out. But with progressive linkage you really want the end carbs sealed tight and not part of the idle equation. Straight, non progressive linkage is a hole different ballgame. I have run a number of different multi carb setups with 3, 4, and 6 carbs. I like the look, but they are a lot of work to get running decent and you leave some HP on the table to get the look. If you don't like swapping out jets and power valves getting things tuned up, run a four barrel. If you want to run a big cam that doesn't have much idle vacuum multi carbs can keep you up at night.
I'm not normally a betting man, but I'd be willing to bet whatever amount you choose that you didn't do this.
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