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Engine Vacuum question...

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Old May 23, 2004 | 02:44 PM
  #1  
Mr.Gearhead's Avatar
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Default Engine Vacuum question...

Hi all,
Just trying to tune the new motor. Break in is finished and I am still doing body work.... I put a vacuum gauge on the Holley 600 today to tune the mixture. I am showing... get this... 30 in Hg. at 850 rpm idle... warmed up. I am a little confused... is anyone else pull this much vacuum? Usually, hooking up a vacuum to the manifold port on the passenger side of the Holley will assist in tuning the air/fuel mixture. But I am already showing 30 in Hg..... any thoughts? :confused:
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Old May 23, 2004 | 03:37 PM
  #2  
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From: Casa Grande AZ
Default Re: Engine Vacuum question... (Mr.Gearhead)

Nope, never had that much ever.
But I think I'd just tune it using what it shows.
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Old May 23, 2004 | 04:19 PM
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Default Re: Engine Vacuum question... (Mr.Gearhead)

faulty gauge.
does it zero off?
i've had to pull off the needle and reset it :rolleyes: then they work OK
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Old May 23, 2004 | 04:34 PM
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Default Re: Engine Vacuum question... (Matt Gruber)

I agree. Bad gauge. :iagree:
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Old May 23, 2004 | 06:46 PM
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Default Re: Engine Vacuum question... (SanDiegoPaul)

yep, sounds a little high......
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Old May 23, 2004 | 07:09 PM
  #6  
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Default Re: Engine Vacuum question... (Sharky Guam)

i have 25 at idle and 15 in gear
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Old May 23, 2004 | 11:47 PM
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Default Re: Engine Vacuum question... (Matt Gruber)

Yep.. it's the gauge. Just went out to the garage and what do you know....? The gauge reads 21 in Hg. just sitting there. I never even noticed... just hooked it up. Maybe it broke during my tuning? Oh well, going to buy another one tomorrow. Sometimes I think I make my small problems too hard to solve... THANKS GUYS!!!!!!! :lol:
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