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too much vacuum advance?

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Old 08-03-2005, 04:49 PM
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too much vacuum advance?

On a stock ford distributor, is the vacuum advance adjustable?

Here what is going on...

If I time it with the vacuum advance connected, & vacuum applied, it will idle great, but starts extremely hard. pops too early...

If I time it with the vacuum advance disconnected, it will idle great, but the second the carb puts vacuum to the advance, it advances to a point where is starts running like complete crap...

I can not find a happy medium...

ideas, anyone...............
 
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Old 08-03-2005, 09:09 PM
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Madmater, the Ford VA's are indeed adjustable; I think they take a 1/8 or 3/16" allen wrench (inserted in the vacuum fitting).

By your description, you might have the vacuum hose connected to the wrong carb port. There should be no vacuum on the hose at idle, and increasing vacuum only when the throttle is opened. The stock 2150 carb port is located under the automatic choke housing. If you're running an aftermarket carb, you can check the ports for vacuum with your finger. Look for the one with no (or very low) vacuum at idle.
 
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Old 08-03-2005, 10:27 PM
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thanks, thelonerangerxlt. I will try to adjust it tomorrow. I am running a Holley 750 carb on an edelbrock torker 2 intake. I used the same distributor when I had a 2bbl on it, and didn't have this problem. The only thing I can think of, is that there is more vacuum on the holley VA port, than on the stock, or something down that road.

which way do I turn it? will clockwise increase or decrease the amount of advance?
 
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Old 08-04-2005, 08:39 AM
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Madmader, the screw changes the sensitivity of the vacuum advance. Turning it clockwise will increase the sensitivity and let the advance come in sooner, and vice-versa. If you think you have too much vacuum advance coming in when starting, it must be either be too sensitive or the carb is giving too much vacuum on the port at idle. Turning it CCW will decrease the VA sensitivity and might help.....

Here's a good read about adjusting the vacuum advance.
http://home.earthlink.net/~bubbaf250/perf/perf02c.html
 
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Old 08-04-2005, 09:04 AM
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Great link, definately going in my truck favorites.
 
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