Author Topic: Vacuum advance - to use or not  (Read 3851 times)

Offline Cudaah

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Vacuum advance - to use or not
« on: February 04, 2008 - 10:07:16 AM »
I have heard different opinions about running vacuum advance or not.  What is the recommendation out here?  What are the advantages or disadvantages of running it.  I am running a crate 360/380 with a 4.10 gear and 3K stall.  My timing is set at 36.25 @ 2200 RPM at the moment without vacuum advance.

:working:




Offline AMXguy

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Re: Vacuum advance - to use or not
« Reply #1 on: February 04, 2008 - 10:23:08 AM »
I'll let you know after I get my didtributor back from being curved to run the vac advance. the advantage as I'm told is better efficiency and smoother operation but not really a performance gain.  I had to do something to get my curve better so I decided to try the vac advance on the shops advice, I don't see how it will hurt anything if you're curved proper.
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Offline GoodysGotaCuda

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Re: Vacuum advance - to use or not
« Reply #2 on: February 04, 2008 - 10:27:44 AM »
Its used for better cruise mileage. Taking it out will see, usually a 1-2mpg drop. Leaving it in you'll get better mileage, just something else you may need to adjust when setting your timing up.
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Offline Cudaah

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Re: Vacuum advance - to use or not
« Reply #3 on: February 04, 2008 - 10:51:00 AM »
Oh yeah I forgot to mention on am using the MP ectronic ignition kit with the orange box

Offline Chryco Psycho

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Re: Vacuum advance - to use or not
« Reply #4 on: February 04, 2008 - 11:03:23 AM »
not using vacuum adavance  allows higher initial timing so it will run better with higher duration cams etc

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Offline 74 340 4speed

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Re: Vacuum advance - to use or not
« Reply #5 on: February 04, 2008 - 12:10:12 PM »
not using vacuum adavance  allows higher initial timing so it will run better with higher duration cams etc
Exactly.  I have mine plugged off.  My car runs better without it.
Andy
1967 Camaro SS: 406 sbc 505 hp/506 ft lbs|4 speed|Posi|3.73s
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Offline matt63

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Re: Vacuum advance - to use or not
« Reply #6 on: February 04, 2008 - 12:24:28 PM »
not using vacuum advance  allows higher initial timing so it will run better with higher duration cams etc
Agreed and if I'm not mistaken the crate 380 has a nasty cam. :naughty:
Matt in Edmonton

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Offline AMXguy

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Re: Vacuum advance - to use or not
« Reply #7 on: February 04, 2008 - 12:34:10 PM »
How do you guys get away with that without your total coming in too fast? I tried a bunch of springs and no matter what I did if I set my initial up where it needed to be then I was all in at 1800-2000 and it ran like crap if I didn't keep the rpm up under load. I would have liked to not messed with the vac advance but I just couldn't get there from here without it.  if it doesn't run as promised when I get my distributor back I might try it again but I hope this does it.
1970 R/T SE Challenger
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Offline MEK-Dangerfield

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Re: Vacuum advance - to use or not
« Reply #8 on: February 04, 2008 - 06:00:27 PM »
I just started useing the vacuum advance this year. I needed to tweak the pod down some, as I was gettng too much adavance at cruising speed. I went from 12.2MPG Hiway, to 13.3MPG. Hey, it was at 65-70MPH with a  440, so I'm not complaining.  :grinno:


  Mike

Mike

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Offline Cudaah

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Re: Vacuum advance - to use or not
« Reply #9 on: February 04, 2008 - 08:04:29 PM »
thanks for everyones input!


Offline ViperMan

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Re: Vacuum advance - to use or not
« Reply #10 on: February 05, 2008 - 09:42:16 AM »
I needed to tweak the pod down some...

What is a pod?


so I'm not complaining.  :grinno:

Geez, for once!  lol - j/k

Jeff
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Offline hemiken

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Re: Vacuum advance - to use or not
« Reply #11 on: February 05, 2008 - 09:53:41 AM »
Hey Jeff,


The guys are talking about the vacuum canister on the distributer buddy. :2thumbs:
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Offline Chryco Psycho

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Re: Vacuum advance - to use or not
« Reply #12 on: February 06, 2008 - 01:17:42 AM »
you can adjust the vacuum advance , there is an allen screw inside the pot , turning counterclockwise reduces advance by approx  1* / turn

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Offline GoodysGotaCuda

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Re: Vacuum advance - to use or not
« Reply #13 on: February 06, 2008 - 10:06:07 PM »
1* per full allen revolution? I may hook mine back up, add a couple degrees in while at cruise.
Build Page: Goody's 'Cuda Build Page
1976 Dodge Warlock
1972 Barracuda - 5.7 Hemi + T56 Magnum

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