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Where does the vacuum advance line go on an old rochestor carb

I have a old rochester carb that I am putting on my old chev, I am trying to stay with an old style and have a 7019014 rochester 4 bbl.
there seems to be no vacuum port on the front of the carb for the distributor vacuum advance. I am trying to stay with the old look and this vacuum line is going to a 56 distributor with a hex diaphragm on the front. where would the vacuum advance line go in.

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  • bs2jvdw May 31, 2009

    thanks for the info. i found on a different sight that the early chevs used a engine vacuum then later changed to using a throtle port vacuum that increased the vacuum as the engine rpm increased to burn the fuel better. straight engine vacuum decreases as the trottle is opened, on this sight it said to play with the springs to use the full machinical advance throught the rpm range.

    this seems to be a pretty good article on distributor advance.

  • Samuel Charles Spriggs May 11, 2010

    For what it's worth, seems I remember a "spacer" (or whatever that thing is called) under the carb with a vacuum port on it.



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Get a tee fitting for the size of the vaccum line and connect the advanced line into an existing line from the carb. Worked for me on one of my old cars.

Posted on May 31, 2009


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