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VACUUM issue

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Old Sep 19, 2011 | 02:28 AM
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Default VACUUM issue

so i've been able to get the turbo on my car, and having a little bit of a vacuum issue. since it re-hooked up the vacuum gauge it's only pulling 3-4psi vacuum under idle. with the old turbo it would pull about 20psi vacuum at idle.

I have the gauge tapped in vacuum source at the map sensor line. it also is t-d to my BOV.

i've been told it might have to do with my camshaft. i'm using speedinc's TU2

Cam Duration Lift LSA
int. exh. int. exh.
TU2 236 236 .587 .587 112.5
it's on a 6.0 with wiseco -25cc pistons

looking for any advice or suggestions
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Old Sep 20, 2011 | 03:31 PM
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started looking for leaks today and didn't find anything. any input would be appreciated
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Old Sep 20, 2011 | 04:38 PM
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i have the TU-3 and get 12 vac at idle.

how does your car run? pinch off the hose before it gets to the map, bov and see if it improves.
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Old Sep 20, 2011 | 07:11 PM
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Originally Posted by madmax4499
i have the TU-3 and get 12 vac at idle.

how does your car run? pinch off the hose before it gets to the map, bov and see if it improves.
what's your compression ratio if you don't mind my asking?
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Old Sep 20, 2011 | 07:16 PM
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9.3 to 1
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Old Sep 21, 2011 | 02:21 AM
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Originally Posted by madmax4499
9.3 to 1
mines supposed to be just under 8.5
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Old Sep 21, 2011 | 08:21 AM
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You are confused

Are you talking psi or Hg?

Big difference (two fold) most talk about vac in mm Hg not psi
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Old Sep 21, 2011 | 08:24 AM
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I have a 232/242 113 on a 10:1 370 and get 10-11 Hg at a 900rpm idle
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Old Sep 21, 2011 | 11:20 PM
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ran it today and it hit 8 and sorry it's def in/Hg



Originally Posted by rotary1307cc
You are confused

Are you talking psi or Hg?

Big difference (two fold) most talk about vac in mm Hg not psi
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Old Sep 22, 2011 | 07:57 AM
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Put the BOV on a separate line from the MAP sensor & gage.
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