Just needing some help

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Inhishands21

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I inherited a 1969 dodge charger from my grandfather. He bought it new, and had it worked on several times. I believe he said it was rebuilt twice. Last rebuild was because previous mechanic left shop rag in distributor hole when he installed the new distributor. Anyway, the car runs very rough. I can adjust the timing and get it to idle smoothly at 950 rpm, but when I reconnect vacuum advance it jumps to 2300. What am I doing wrong? (I'm just a farmhand with general knowledge of mechanics and keep it running smarts) My main love is the animals, but I don't want to throw away a good vehicle if I can fix it.
 
Sounds like whoever messed with it last had the vac advance connected to manifold vacuum instead of ported
 
Not that I'm much help but that's pretty much how to differentiate Magnums from LA engines.
 

Doesn't really mean anything other than terminology. It doesn't help your situation other than trying to inform you how Chrysler does it. Magnum motors are designated in liters and NON magnum blocks (LA engines) are designated in cubic inch.
 
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You have timing coming from both vacuum advance and mechanical advance... When you plug the hose in to the vacuum port it brings in timing, that timing causes the rpm's to increase, when the rpm's increase that causes the mechanical advance to bring in more timing..... Which causes the rpm's to climb even higher....

The problem is originally the vacuum advance was connected to ported vacuum, that means there is no vacuum at idle, it starts coming in at around 1200 rpm's....
The port on the side of the carb is manifold vacuum, depending on your actual carb there is probably a ported vacuum source on the front edge of the base plate...

FWIW Sorry to hear of your grandfathers passing but he left you a cool car that should remind you of him for years to come..
 
You have timing coming from both vacuum advance and mechanical advance... When you plug the hose in to the vacuum port it brings in timing, that timing causes the rpm's to increase, when the rpm's increase that causes the mechanical advance to bring in more timing..... Which causes the rpm's to climb even higher....

The problem is originally the vacuum advance was connected to ported vacuum, that means there is no vacuum at idle, it starts coming in at around 1200 rpm's....
The port on the side of the carb is manifold vacuum, depending on your actual carb there is probably a ported vacuum source on the front edge of the base plate...

FWIW Sorry to hear of your grandfathers passing but he left you a cool car that should remind you of him for years to come..
Thank you. Those were my thoughts exactly. (FWIW)
 
Yep as someone mentioned above, the engine may have been tuned for manifold vacuum, and then you attached to ported vacuum and it caused the timing to go higher. I'm not familiar with timing ports on 2bl carbs. More knowledgable people will help you out.
Super clean engine bay!
Show the rest of the car!
 
Okay, the yellow port connects to the choke pull-off which is green... Vacuum advance connects to the nipple that should be near the blue arrow under the float bowl...

Oh, if you decide to throw it away, throw it my way... LOL...


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Yep as someone mentioned above, the engine may have been tuned for manifold vacuum, and then you attached to ported vacuum and it caused the timing to go higher. I'm not familiar with timing ports on 2bl carbs. More knowledgable people will help you out.
Super clean engine bay!
Show the rest of the car!
Installing new plugs this morning

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