which vacuum line is for timing on an edelbrock carb?
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Car: 88 IROC - 86 Trans Am
Engine: L98 Carbed - 350 Carbed and boosted
Transmission: auto - T5
which vacuum line is for timing on an edelbrock carb?
there are 2 vacuum ports on the front, which one is for the timing?
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Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
should be the one on the passenger side. the one that's higher up from hte base of the carb. it has no vacuum at idle.
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Car: yy wife, crazy.
Engine: 350, Vortecs, 650DP
Transmission: TH-350
Axle/Gears: 8.5", 3.42
Uh...... you DO want vacuum at idle for a vacuum advance dist.
Why else would it be called vacuum advance?
I don't recall which one it is, but if you have a vacuum gauge it's easy to find. Hook it up and if there's vacuum at idle, but none when you quickly open the carb to wide open throttle, then that's the one you want.
It's been so long since I've messed with one I don't remember which one it is exactly.
Why else would it be called vacuum advance?
I don't recall which one it is, but if you have a vacuum gauge it's easy to find. Hook it up and if there's vacuum at idle, but none when you quickly open the carb to wide open throttle, then that's the one you want.
It's been so long since I've messed with one I don't remember which one it is exactly.
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I don't recall which is which offhand. With the car at idle, just uncap them one at a time. One will have vacuum, the other will not. Once you know which one does not, you've got it.
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Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
Originally posted by AJ_92RS
Uh...... you DO want vacuum at idle for a vacuum advance dist.
Why else would it be called vacuum advance?
I don't recall which one it is, but if you have a vacuum gauge it's easy to find. Hook it up and if there's vacuum at idle, but none when you quickly open the carb to wide open throttle, then that's the one you want.
It's been so long since I've messed with one I don't remember which one it is exactly.
Uh...... you DO want vacuum at idle for a vacuum advance dist.
Why else would it be called vacuum advance?
I don't recall which one it is, but if you have a vacuum gauge it's easy to find. Hook it up and if there's vacuum at idle, but none when you quickly open the carb to wide open throttle, then that's the one you want.
It's been so long since I've messed with one I don't remember which one it is exactly.
you do it your way and you reverse the mechanism operation. at idle it will add all the timing. then when you open the throttle blades it will retard the timing.
Last edited by mrr23; 04-30-2003 at 08:36 PM.
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Car: yy wife, crazy.
Engine: 350, Vortecs, 650DP
Transmission: TH-350
Axle/Gears: 8.5", 3.42
OK... here's a pic I found at (can you guess?) www.edelbrock.com
As you'll see, the port on the passenger side is for Timed Vacuum Port for emission controlled vehicles.
The one on the driver's side is for Manifold Vacuum Port for non-emission controlled engines.
Here are some instructions that they give.
That should clear it up for ya.
I guess it really revolves around what type of distributor you have. I've always had ones that used a full vacuum source, so there was vacuum at idle, but slowly diminished as the RPM increased.
mrr23 has obviously used more timed vacuum advance systems.
So I guess we both were right..... but now you have to find out what system YOU have.
As you'll see, the port on the passenger side is for Timed Vacuum Port for emission controlled vehicles.
The one on the driver's side is for Manifold Vacuum Port for non-emission controlled engines.
Here are some instructions that they give.
Before Removing Old Carburetor
Determine if the distributor vacuum advance it timed (no vacuum at idle) or full (vacuum present at idle).
With the engine fully warmed up and idling, pull the vacuum hose off of the carb and "feel" for vacuum by putting your finger on the vacuum port. If your distributor has timed vacuum advance, hook the distributor vacuum hose up to the passenger side vacuum port on the carburetor. If it has full vacuum advance, hook it up to the driver's side vacuum port.
Determine if the distributor vacuum advance it timed (no vacuum at idle) or full (vacuum present at idle).
With the engine fully warmed up and idling, pull the vacuum hose off of the carb and "feel" for vacuum by putting your finger on the vacuum port. If your distributor has timed vacuum advance, hook the distributor vacuum hose up to the passenger side vacuum port on the carburetor. If it has full vacuum advance, hook it up to the driver's side vacuum port.
I guess it really revolves around what type of distributor you have. I've always had ones that used a full vacuum source, so there was vacuum at idle, but slowly diminished as the RPM increased.
mrr23 has obviously used more timed vacuum advance systems.
So I guess we both were right..... but now you have to find out what system YOU have.
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Car: 88 IROC - 86 Trans Am
Engine: L98 Carbed - 350 Carbed and boosted
Transmission: auto - T5
well i hokked it up to the passenger side, it has vacuum at higher rpm's, the other one always has vacuum, my distributor is vacuum advance. with it hooked up to the passenger side now, i just dont feel the power, i think ill try the drivers side then?
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I believe the only difference between the two ports occurs at idle. Off idle, ported vacuum is the same as manifold vacuum. I don't see why it would give you a lack of power. All that hooking it up to the other port will do is give you more advance at idle. Is this a new carb installation, or did you just have to remove it for something and are putting it back on?
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Car: yy wife, crazy.
Engine: 350, Vortecs, 650DP
Transmission: TH-350
Axle/Gears: 8.5", 3.42
Yea.. Mike's right. There shouldn't be any difference when you push the go pedal. Seems as though you've got other problems besides the vacuum advance.
The only difference with the two is vacuum at idle. I've always used the driver's side because every car I've ever had a carb on had a radical cam and it just idled better.
The only difference with the two is vacuum at idle. I've always used the driver's side because every car I've ever had a carb on had a radical cam and it just idled better.
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Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
yes there are both types of distributors. emmisions years started as early as 1973. but my 79 z28 needed the part time vacuum. what you may want to do is find a vacuum diagram for the engine the distributor came from. you will find very few of the full time advance distributors.
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Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Originally posted by mrr23
yes there are both types of distributors.
yes there are both types of distributors.
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Car: 1986 pontiac TA
Engine: 360 HSR
Transmission: 700r4 3300 yank converter
Axle/Gears: 3.27 9 bolt
ok i'll clarify for you. there are 2 types of vacuum advance pots. one where it advances as vacuum increases. and the other that advances as vacuum decreases. that is what needs to be found out. and even then some pots have a 10* advance and some have a 16* advance. usually the mechanical advance part has 10* capability. but again most will be the one that advances as vacuum increases.
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Car: 1989 Chevy Camaro
Engine: 350
Transmission: automatic
Re: which vacuum line is for timing on an edelbrock carb?
I know that this post is very old. But i have a problem with the car dying when put into gear its a camaro and was computerized.. i had to put a lock up kit on the transmission was wondering what side what went to. i'd like to have my car run properly. any help would be apprecitated.
#18
Re: which vacuum line is for timing on an edelbrock carb?
1985 K5 Blazer, stock 350 with MSD vacuum advance distributor (HEI) part number 8362. 1906 edelbrock ASV2 Carb. Just got off the phone with edelbrock tech. Tech says that you want to use port on the passenger side (emissions side). If you check with a vacuum gauge, you will see no vacuum at idle (pass side). Driver side (non-emissions side) you will see vacuum at an idle. Tech at edelbrock I spoke to said that the instructions are poorly worded and everyone in the tech department is trying to get edelbrock to change the way it’s worded. Having said all that, I called MSD and they say you Do want vacuum at an idle???? Then I found this article from superchevy. Read this article!!! I get it now!
http://www.superchevy.com/how-to/add...nition-timing/
hope this helps someone one day!
http://www.superchevy.com/how-to/add...nition-timing/
hope this helps someone one day!
Last edited by 1929ModelA; 01-21-2021 at 01:33 PM. Reason: Posted incorrect info
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Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: which vacuum line is for timing on an edelbrock carb?
1985 K5 Blazer, stock 350 with MSD vacuum advance distributor (HEI) part number 8362. 1906 edelbrock ASV2 Carb. Just got off the phone with edelbrock tech. Tech says that you want to use port on the passenger side (emissions side). If you check with a vacuum gauge, you will see no vacuum at idle (pass side). Driver side (non-emissions side) you will see vacuum at an idle. Tech at edelbrock I spoke to said that the instructions are poorly worded and everyone in the tech department is trying to get edelbrock to change the way it’s worded. Having said all that, I called MSD and they say you Do want vacuum at an idle???? Then I found this article from superchevy. Read this article!!! I get it now!
http://www.superchevy.com/how-to/add...nition-timing/
hope this helps someone one day!
http://www.superchevy.com/how-to/add...nition-timing/
hope this helps someone one day!
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