Is this the intake manifold vacuum?

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Fitz68

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Another dumb question for all you pro's out there. I'm changing out my manual drum brakes on my 68 dart (318ci) and converting to power and disc in the front. I'm trying to figure out where the booster vacuum hose would connect to on the intake manifold. Is what I have circled where I would connect it? It seems like it's a valve that has like 5 outlets and two of them are just capped. Could I use one of them?
 

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Fitz68 said:
Another dumb question for all you pro's out there. I'm changing out my manual drum brakes on my 68 dart (318ci) and converting to power and disc in the front. I'm trying to figure out where the booster vacuum hose would connect to on the intake manifold. Is what I have circled where I would connect it? It seems like it's a valve that has like 5 outlets and two of them are just capped. Could I use one of them?
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Yes, that's intake manifold vacuum from that "port", but the brakes need a larger diameter hoses (I can't remember the exact size, but I want to say like 5/16" diameter, most of the little "arms" coming off of that port are closer to 1/8" diameter.

You can find other vacuum fittings with the larger nipple in the center and a few smaller ones coming off the side. That way you can get the proper diameter and volume of vacuum to the booster and also connect any of the other accessories back up to the smaller ones.

You can also get the smaller diameter manifold vacuum ports from the bottom base plate in the carb. Make sure that it is on the base plate for intake vacuum.

The one above the base plate is ported vacuum that is used for the vacuum advance for the distributor...
 
This is REALLY helpful. Thank you all. :) Now just cross your fingers I can figure out how to fit the booster.
 
Ok, so rather than the first pic where I'm using the vacuum tree potentially to connect to the brake booster. With this pic am I better off capping the circled part at the valve cover and rerouting that line from the carb to the brake booster? I finally got my hard lines in and the brakes bled! Last step is to get the vacuum line setup and determine if I have enough vacuum to avoid an electric vacuum pump. I feel pretty good about it given it's the stock cam though. Thanks for the help!
 

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Fitz68 said:
Ok, so rather than the first pic where I'm using the vacuum tree potentially to connect to the brake booster. With this pic am I better off capping the circled part at the valve cover and rerouting that line from the carb to the brake booster? I finally got my hard lines in and the brakes bled! Last step is to get the vacuum line setup and determine if I have enough vacuum to avoid an electric vacuum pump. I feel pretty good about it given it's the stock cam though. Thanks for the help!
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No that is your PCV valve ....DO NOT CONNECT THERE! leave that hooked up how it is.....Just put a single large hose fitting in the manifold where krazykuda is telling you and connect the hose to the power booster
 
Thanks Brown and Krazy--one last question--so I've been reading up on the vacuum fitting since I need to obtain one that has the large fitting coming out the top. Some of the material I came across indicated that I may not have enough vacuum to run the big port out of that tree which has the other hoses already connected. It mentions other intake ports that could be used as a dedicated line to the power booster, but I think my other inlet is being used to support the AC unit. (can see in the pic) Does anyone think this is wrong and I should be able to just plumb it into the big port of the new tree? Again, it's stock 318 with standard cam.
 
Just put one in like krazykuda said...one with big port straight up and run it to the vacuum booster.....That is the best place with the greatest amount of vacuum you can get.....With your "standard cam" as you say it will have plenty of vacuum...probably around 19-21....The problem with low vacuum happens when you have a huge cam.....which you do not...You will be fine
 
Ok, so I have the new vacuum tree installed. Per the first picture you can see I have two lines running to the distributor plus a tiny line(leftmost in the picture)...and now I have the big 3/8 line running out the top and an additional 1/4 port that I have taped over right now with electric tape because I don't have a plug for it. I have a 3 foot 3/8 fuel line hose running from the vacuum tree to the brake booster. With this current setup I'm getting a steady 16 psi reading on my vacuum pump gauge and my break pedal is basically going right to the floor.

Is this an indication that I don't have enough vacuum to run the booster after all and need an electric vacuum pump or could it be because it's a fuel line...or because the hose is 3 feet..or because....?? any thoughts?
 
16 psi is plenty of vacuum to run the booster...nothing wrong with length or type of hose......Sounds like you have other problems with brakes....Did you bleed the entire brake system after you changed over to the new style brakes? You need to get all the air out....start on RR then got to LR then RF then finish with the LF
 
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