I know multi carb stuff is almost beat to death and everybody has their technique and/or opinion. Didn't find anything on how to set up the linkage itself when I did a search though! I'll be running 3 94's (2 sec., 1 pri.), progressive linkage, on a Offy intake for a '56 Pontiac. What I need to know is how to set up the progressive linkage: 1. What part of it do I change to set where the secondaries begin to open? 2. Where do I set the stops to make sure the the secondaries are all the way open when the primary is all the way open? 3. What type of linkage should I use for the chokes? I wanna run a manual choke on them, with a choke cable (just primary or all three?) 4. Any other useful info??? Thanks guys! Johnny
Number three first, choke the center one only, thats why its called the primary. Then, have someone step the gas pedal all the way down. Adjust the linkage so the primary is all the way open, then set the secondaries so they are all the way open. Release the gas pedal and hope they all close, adjust spring pressure to make that happen. Its really rather simple when you start playing with it.
Mine is set up with the center carb as the primary with a manual choke and it's own return spring. The pedal works the linkage on the driver side from closed to WOT. The outside carbs, secondaries have a different ****erfly angle to ensure they stay closed and have their own return spring. The secondaries are linked together on the p*** side My primary carb has an extended throttle shaft that sticks out the p*** side with an adjustable arm on it that works the other two carbs. The linkage in the picture I stole from Speedway shows all the parts that go on the p***enger side only. I set my stopper to approx 3/4 throttle on the primary carb, the last 1/4 opens the secondaries from closed to WOT. you adjust the stopper and the hole on the arm to get enough travel to open the secondaries all the way. Clear as mud??:?
Regarding the chokes..... I understand only one NEEDS to function, but would it help my idle if the chokes are also closed on the secondaries? I'm thinkin' less air would leak by the throttle plates and help even out the idle settings. Does that make sense at all? If I do run only the primary choke, I've heard that the choke plates still need to be in the secondaries to smooth airflow. How do I get them to stay open? I don't trust the return spring alone to do that, and I'm sure they'll be subject to some pretty heavy vibration! Johnny
Hello...Here is a picture of the way I set them up..What is important is the primary throttle lever has to move twice the distance on the secondary, so the secondary catchs up and they both will open all the way..Notice that the primary throttle linkage is twice the length of the secondary, this is where the 2 to 1 works.. Hope this helps.. Duane
You can take the chokes out of the secondaries. But its best to get the thicker throttle plates and block of the idle mixture screws on the secondary carbs(outer two).
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