Why does the vacuum advance have two vacuum lines?
Mar 26, 2012 | 03:30 PM
#1
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Why does the vacuum advance have two vacuum lines?
Why does the vacuum advance have two vacuum lines? When switching carbs, I've seen guys just use one, and plug other one, and then I've seen guys use both with a "T" into one line. What's the best way to do it? Thanks, Dean
Apr 19, 2012 | 10:24 AM
#3
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One connection on the distributor is the standard vacuum advance while the other is to advance the timing to 15 degrees BTDC to save fuel. I have the regular Weber 32/36DGAV carb on mine and only use the one vacuum hose to advance timing.
Apr 23, 2012 | 08:24 AM
#4
Technically, you could run without either vacuum advances hooked up, but your power and fuel economy will suffer.
If you are only going to run one advance off of the distributor, you want to run the advance port closest to the radiator back to the carb (and cap the other port on the distributor). On a weber, it hooks up to the only vacuum port on the carb. On a factory carb (desmogged setup), run it to any vacuum port and cap the rest on the carb.
If you are going to run both advances off the distributor, follow the above steps on the port closest to the radiator and run port closest to the motor to a manifold vacuum advance and cap off all the unused manifold vacuum ports. This is how I have mine setup and I run perfectly fine.
Here's a picture that I found online:
"Ported Vacuum/Normal advance" goes to the carb vacuum advance.
"Manifold Vacuum/Idle advance" goes to the manifold vacuum advance port.
Everything else is capped
If you are only going to run one advance off of the distributor, you want to run the advance port closest to the radiator back to the carb (and cap the other port on the distributor). On a weber, it hooks up to the only vacuum port on the carb. On a factory carb (desmogged setup), run it to any vacuum port and cap the rest on the carb.
If you are going to run both advances off the distributor, follow the above steps on the port closest to the radiator and run port closest to the motor to a manifold vacuum advance and cap off all the unused manifold vacuum ports. This is how I have mine setup and I run perfectly fine.
Here's a picture that I found online:
"Ported Vacuum/Normal advance" goes to the carb vacuum advance.
"Manifold Vacuum/Idle advance" goes to the manifold vacuum advance port.
Everything else is capped
Apr 25, 2012 | 11:46 AM
#5
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Joined: Feb 2011
Posts: 199
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Technically, you could run without either vacuum advances hooked up, but your power and fuel economy will suffer.
If you are only going to run one advance off of the distributor, you want to run the advance port closest to the radiator back to the carb (and cap the other port on the distributor). On a weber, it hooks up to the only vacuum port on the carb. On a factory carb (desmogged setup), run it to any vacuum port and cap the rest on the carb.
If you are going to run both advances off the distributor, follow the above steps on the port closest to the radiator and run port closest to the motor to a manifold vacuum advance and cap off all the unused manifold vacuum ports. This is how I have mine setup and I run perfectly fine.
Here's a picture that I found online:
"Ported Vacuum/Normal advance" goes to the carb vacuum advance.
"Manifold Vacuum/Idle advance" goes to the manifold vacuum advance port.
Everything else is capped
If you are only going to run one advance off of the distributor, you want to run the advance port closest to the radiator back to the carb (and cap the other port on the distributor). On a weber, it hooks up to the only vacuum port on the carb. On a factory carb (desmogged setup), run it to any vacuum port and cap the rest on the carb.
If you are going to run both advances off the distributor, follow the above steps on the port closest to the radiator and run port closest to the motor to a manifold vacuum advance and cap off all the unused manifold vacuum ports. This is how I have mine setup and I run perfectly fine.
Here's a picture that I found online:
"Ported Vacuum/Normal advance" goes to the carb vacuum advance.
"Manifold Vacuum/Idle advance" goes to the manifold vacuum advance port.
Everything else is capped
Apr 25, 2012 | 12:59 PM
#6
Those are the only two vacuum lines involved in a desmogged motor. If you are retaining the factory Smog equipment and vacuum hoses then I can't help you there; check out the FSM for a diagram
Nov 3, 2012 | 09:52 AM
#7
You dont by chance have a pic of which ports on the stock carb the hoses whould go to do you?
I am balls deep in a desmog and I cant figure out which ports on the carb both lines go to.
Thanks
I am balls deep in a desmog and I cant figure out which ports on the carb both lines go to.
Thanks
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TokyoD23
95.5-2004 Tacomas & 96-2002 4Runners
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Jul 12, 2015 06:01 AM
3031, advance, connection, didtributor, distributor, hose, idle, line, manifold, pict, pictures, ported, toyota, vacuum, weber
