Re: Holley 4160 Metering Block vacuum line?
[Re: sharpie]
#317066
05/13/09 02:01 PM
05/13/09 02:01 PM
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Joined: Jan 2003
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CJK440
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Thats ported vacuum which should have zero vacuum at idle and what your vacuum advance should be connected to.
You can probably drill it out and press/epoxy in a metal tube.
2017 Contusion Blue Challenger T/A 392 M6 "BLKNBLU"
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Re: Holley 4160 Metering Block vacuum line?
[Re: sharpie]
#317067
05/13/09 02:04 PM
05/13/09 02:04 PM
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Joined: Jan 2003
Posts: 4,737 Moved to N.E. Tennessee
GomangoCuda
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The one on the base plate is manifold vacuum instead of ported vacuum. Vacuum advance is not normally connected to manifold vacuum. A few people like to use manifold vacuum and who knows there may infact be combinations that it would work good on.
In theory, there is no difference between theory and practice. In practice, there is.
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Re: Holley 4160 Metering Block vacuum line?
[Re: RapidRobert]
#317072
05/13/09 07:48 PM
05/13/09 07:48 PM
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Joined: Oct 2003
Posts: 7,506 Az
Crizila
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If you are driving on the street and your distributor has a vacuum advance unit on it, use it. Most Mopars ( from the factory ) ran ported vacuum. If you are running stock stuff, run ported vacuum. If you are running a pretty hot cam and have idle issues. switch over to manifold vacuum. The extra advance at idle will help with idle quality. Mileage will be better if you use the vacuum advance, not to mention the motor will run cooler.
Fastest 300
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Re: Holley 4160 Metering Block vacuum line?
[Re: Crizila]
#317073
05/13/09 07:56 PM
05/13/09 07:56 PM
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Posts: 5,746 Ontario, Canada
Dodgem
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Quote:
If you are driving on the street and your distributor has a vacuum advance unit on it, use it. Most Mopars ( from the factory ) ran ported vacuum. If you are running stock stuff, run ported vacuum. If you are running a pretty hot cam and have idle issues. switch over to manifold vacuum. The extra advance at idle will help with idle quality. Mileage will be better if you use the vacuum advance, not to mention the motor will run cooler.
People who know nothing about tuning a performance car compensate by putting the vacuum advance on manifold vacuum. It helps hold the idle for those with lack of tuning ability. But at WOT there is no vacuum and you give up a huge amount of Performance! Some people should not be offering up advice period!
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Re: Holley 4160 Metering Block vacuum line?
[Re: Dodgem]
#317074
05/14/09 10:58 AM
05/14/09 10:58 AM
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Joined: Apr 2007
Posts: 560 MI
marklock
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I tried too hard for a custom title
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Re: Holley 4160 Metering Block vacuum line?
[Re: marklock]
#317075
05/14/09 11:06 AM
05/14/09 11:06 AM
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Joined: Jan 2003
Posts: 9,982 Ansonia, CT
CJK440
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One problem I have seen with using manifold vacuum is that get into a loop where
1-RPM fluctuates and affects vacuum 2-which affects the ignition timing at idle 3-which affects the RPM, 4-go back to 1.
Ported vacuum works just like manifold vacuum to give you the same vacuum timing affect during cruise, but "shuts off" at idle.
One other thing, if you do have vacuum at the ported vacuum barb at idle you can be reasonably sure your idle screw is opened too far and you are going to have other drivability/tunability problems.
2017 Contusion Blue Challenger T/A 392 M6 "BLKNBLU"
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