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Author Topic:   carb idle
posted April 22, 2004 07:30 PM
I have a rochester 2b on a chevy 406. I have my engine idle at about 1400-1500 rpm when out of gear, but when i put the car in gear it dies almost instantly. I have tried the idle air mixture screws and they dont seem to have any affect on this. It idles fine out of gear but wont even try to idle when in gear. Any ideas??????

Ego Racing
posted April 22, 2004 08:35 PM
What type of transmission? Torque Converter?

posted April 23, 2004 07:08 PM
If it's idling at 1500, then your butterflies are too far open and you're not actually on the idle circuit. Drill 1/8" holes in the butterflies (or enlarge the ones that are there) so you can back the idle screw down and still get it to idle about 1200. Then set your idle mixture screws.
At 1500, the 2G is actually in its midrange circuit and dropping it in gear is bringing it back down to the idle circuit which probably isn't getting any signal and/or the mixture screws are outta whack.
Also the air bleeds in the booster assembly may need to be decreased in size to richen up the idle circuit so it will idle at the lower rpm.

Hope that helps,

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