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Old Apr 4, 2001 | 09:51 PM
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killer4x4
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vacuum tuning

 
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Old Jun 18, 2001 | 08:15 PM
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vacuum tuning

I came accross an article the other day about vacuum tuning. Not as complete as I would like, but in it was mentioned about how to tell if your carb was jetted too rich, "...turning either of the mixture screws all the way lean, should kill the engine. If not, your too rich. This may require re-jetting, or drilling the primary butterflies to add more idle air..." I turned the screws all the way in. It ran rough, but did not kill. Do I need to re-jet my carb. or is there a bigger picture I am missing?
I have, as far as I know, A stock 360, 2V Autolite carb, c4 tranny.

Thank you for any and all information.

 
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Old Jun 21, 2001 | 11:53 PM
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vacuum tuning

back the idle off a bit first, you might be off the idle. As the butterflys open, they start pulling gas from passages on the side above the idle passages, if the butterflys are open too far that could be the problem. You might have to play with the timming at the same time to get idle high enough if you running above the idle passages.

I've heard of the fastest idle method, turn the idle stop screw down, turn the idle mix screw to highest idle, turn idle stop screw down again... until you get the right idle speed (this was from a hot rod tv show, so it may not work for stock setups)
 
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Old Jul 9, 2001 | 01:35 PM
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vacuum tuning

It turns out I did have the idle turned too far in, that was just to keep it running. I have put rebuilt heads on, as well as other things, and I was able to run at the same idle speed but the butterflys are now closed, and it does kill when I turn in the mixture screws. Thanks
 
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