12-26-2019, 08:41 PM | #1 |
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Vacuum port
I only have on vacuum port on my Offy dual carb manifold.
Can I use it without a T for the carbs? I’m not sure if at idle there is a vacuum needed for the dual carbs.
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12-26-2019, 09:20 PM | #2 |
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Re: Vacuum port
What engine and dizzy ya running? You could always tap one if needed. If needed. 94 Carbs have a base vacuum hole, but really not sure what your asking?
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12-27-2019, 11:58 AM | #3 |
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Re: Vacuum port
I've never seen a 94 carb on a Ford with a vacuum port at the base. '49 to '56 94 type carbs had a port higher up for the distributor advance (loadomatic), but it was not actual manifold vacuum. A lot less.
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12-27-2019, 10:58 PM | #4 |
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Re: Vacuum port
What do you need the second port for? The old flatheads had two ports. One for the distributor and the other for the windshield wipers. Assuming that when you went with dual carbs, you would go to an electronic distributor.
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12-28-2019, 09:28 AM | #5 |
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Re: Vacuum port
I disconnected wiper and use the Offy port for carbs. I have a bubba 11a distro and skip coil.
I want to attach a vacuum gauge to run some tests. As mentioned currently vac port is used for both carbs.
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12-28-2019, 11:36 AM | #6 |
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Re: Vacuum port
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I would disconnect the carbs from the intake and use the manifold port for the vacuum gauge. |
12-28-2019, 02:01 PM | #7 |
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Re: Vacuum port
What carbs are you running that require a manifold vaccum connection?
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12-28-2019, 04:32 PM | #8 |
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Re: Vacuum port
Edlebrock
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12-29-2019, 07:39 AM | #9 |
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Re: Vacuum port
The Offy vacuum port should go to the distributor vacuum brake. If you place a vacuum gauge there the vacuum will be the highest at idle 18-20 and decrease as engine speed increases. I would cap the Edlebrock vacuum ports if you place a vacuum gauge on the Carb port and increase engine speed the vacuum there should increase with RPM.
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12-29-2019, 08:17 AM | #10 | |
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Re: Vacuum port
Quote:
You are correct. The Offy vacuum goes to distributor. I wanted to know to run vacuum test, do I have to T this connection. Or can I disconnect the distributor and use the line strictly for the vacuum gauge. Again thanks for your patience.
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12-29-2019, 10:33 AM | #11 |
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Re: Vacuum port
You can disconnect and use the port for the vacuum gauge. Are you wanting to check idle vacuum?
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12-29-2019, 11:23 AM | #12 |
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Re: Vacuum port
I was hoping to adjust the carbs.
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