What is the normal vacuum reading for a 5.0?

Discussion in 'Fox 5.0 Tuning' started by Dr Ron, Sep 30, 2006.

  1. Dr Ron New Member

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    I think that I may have a vaccumm leak after swaping intake/plenum combo. What is the factory vaccuum reading?

    thanks,
    Ron
    Dr Ron, Sep 30, 2006
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  2. Snikt89GT New Member

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    A lot of people seem to say that around 15 inches is normal. I tested this on my car today and I got 15-20 inches at idle.

    I think if you are 13-20 you are fine, below 13 is a problem
    Snikt89GT, Oct 1, 2006
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  3. VG30DE Founding Member

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    Depends on your cam and TB. Normal stock should be 14-16
    VG30DE, Oct 3, 2006
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  4. poneypower89 Now everyone in the world will know I wanna bang t

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    My car is bone stock save for a vortech blower, and full exhaust. I see 18-19 inches of vaccum at idle.

    when my BOV nipple broke causing a vaccum leak I only seen 11-13... so I would say the 14-16 would be ever so no enough... but thats just me. Maybe it changes with the years 5.0 seeing how ford put slightly different cams in there througout the 5.0 run.
    poneypower89, Oct 3, 2006
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  5. millhouse Founding Member

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    13-14 is way low for a stock cam. I'd say normal is probably more along the lines of 18-20+.

    I myself pull 14-15 inches of vacuum at idle with an F-cam and 1.7 rr's.
    millhouse, Oct 4, 2006
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  6. VG30DE Founding Member

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    I pull 8-10 with my comp XE276 lol.. and thats at 1100rpm
    VG30DE, Oct 4, 2006
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  7. coupecop New Member

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    how do you check the vac
    coupecop, Oct 4, 2006
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  8. MARX91 New Member

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    MARX91, Oct 5, 2006
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  9. Muscleford New Member

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    I am carbd but am pulling 18" vacuum at idle. It was only 15" until i adjusted the idle mixture. I am running the "B" cam and a 4180C with a 6.5 power valve, lightest secondary spring Holley has, and the primary is jetted two sizes up and the secondary metering plate is drilled two sizes up.

    George
    Muscleford, Oct 19, 2006
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