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Old 03-22-2009, 10:23 PM   #1
pokethesmot
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vacuum

what should my vacuum level be at i have a 400sbc
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Old 03-22-2009, 10:26 PM   #2
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Re: vacuum

To many variable to even state what it should be.

http://www.centuryperformance.com/tu...e-spg-148.html
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Old 03-23-2009, 06:44 AM   #3
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Re: vacuum

so all i need to tune my carb is just a vacuum gauge
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Old 03-23-2009, 03:39 PM   #4
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Re: vacuum

you should also use a tach to adjust the idle rpm since they will probably change when you start adjusting the idle mixture. You want the idle to be set at the factory speed and remain constant through-out the adjustment...otherwise your vacuum readings wont be accurate.
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Old 03-23-2009, 03:48 PM   #5
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Re: vacuum

Quote:
Originally Posted by 83burban View Post
you should also use a tach to adjust the idle rpm since they will probably change when you start adjusting the idle mixture. You want the idle to be set at the factory speed and remain constant through-out the adjustment...otherwise your vacuum readings wont be accurate.
Yah I discovered my truck was idling around 500 rpm

Bumped it up to about 900 and now its a lot better.
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Old 03-25-2009, 04:26 PM   #6
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Re: vacuum

wow that was interesting think i'm going out and getting me one of those
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