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Discussion Starter #1 (Edited)
Only when warm and not consistantly I get just the lightest weep of fuel come out the main jet @ idle 750 rpm. Not enough to change the way it runs but its there. I tried float level, power piston spring, power piston adjustment, needle seat, I even swore at it. Its like vacume sucks it out or preasure pushes it. Its just a slight tiny tiny drip once every minute. Any thoughts? Its a mid 70s Q-jet on a mild cam 350
 

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“We also change the accelerator pump and install a larger needle and seat,” Valdez adds. “One of the most important things we modify is the idle circuit. A circle track race motor has a bigger camshaft with longer duration and higher lift than a stock cam, so they have different needs. You have to set up the baseplate so that it allows more air for idling so you don’t expose the throttle plates out of the transfer slot and get nozzle drip.

http://www.circletrack.com/techarticles/ctrp_0607_quadrajet_tech/

Chris,
Sounds like nozzle drip. If your initial timing is not high enough, the throttle blades will be too far open, actually causing you to activate the main metering system. This can also result from trying to use a small block Q-jet on a big block. The big block carbs have what's called a fixed idle air bypass. It allows extra air to bypass the venturis, so that the throttle blades can be nearly closed at idle. What carb # are you using?? (it should be stamped on the main body of the carb behind the throttle linkage, drivers side). What is your initial timing?? If you have too much mechanical advance in the distributor, resulting in a low amount of initial used, you may need to recurve the distributor. Another way to get more advance at idle, is to use vacuum advance from a full manifold source. This will allow you to idle at the same RPM, with a smaller throttle opening.


http://www.v8buick.com/archive/index.php/t-62194.html
 

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