[Taylorcd]

Greetings everyone. I recently inherited a 68 Malibu, and I am not as mechanically car-savvy as I need to be for such a project. It has been a struggle for the last few months, on fix leads to other problems, and I think my newest issues are my fault. The engine is the stoke 307, I got a new Edelbrock intake and 4bbl carb for Christmas. I have installed them but I am not sure my vacuum hoses are ran properly. I have the break and a steel tube, I believe it is the trans tube, but if I am wrong please teach me, to the fitting into the back of the intake. I capped the backport of the carb. I have the distributor tube going to the front of the carb, but there are two options for a 600cfm carb. I currently have the tube in the higher of the two ports. Do I need to change any configurations? I am not sure what all information I could provide to help you decipher my situation, but I appreciate any help I can get.

 

[oldcutlass]

2 types of vacuum, ported - no vacuum at idle and manifold - full vacuum at idle. The brake booster is tied to the 3/8 manifold vacuum port on the back of the carb. The distributor can be tied to either manifold or ported on the front of the carb. The transmission is tied to manifold vacuum either at the front of the carb or off one of the manifold runners. A/C ducts reservoir are tied to manifold vacuum.

 

[Taylorcd]

Here are a couple pics of the current setup. I will have to find a fitting to put the brake booster into the carb.

 

[mark f]

Your brake booster vacuum looks like it is coming out of the manifold port, which is where it should be.

 

[Taylorcd]

Your brake booster vacuum looks like it is coming out of the manifold port, which is where it should be.

Yes it is coming out of the manifold. That is how it was on the old manifold as well.

 

[oldcutlass]

Yes it is coming out of the manifold. That is how it was on the old manifold as well.

With your new info pics, your connections are fine.

 

[Taylorcd]

With your new info pics, your connections are fine.

Do you think the front port is correct also? Basically just the distributor going to that one. Thank you.

 

[David Ray]

Use a stop plate to restrict the vacuum advance degrees, THEN, connect to the driver side vacuum port.

Complete instructions, FREE NO ADS: [email protected]

 

[oldcutlass]

Do you think the front port is correct also? Basically just the distributor going to that one. Thank you.

I prefer the drivers side port as Dave suggested above. Do note that the ported vs manifold vacuum selection for vacuum advance has been debated for decades. There is no right answer if the car idles well.

 

[Taylorcd]

I prefer the drivers side port as Dave suggested above. Do note that the ported vs manifold vacuum selection for vacuum advance has been debated for decades. There is no right answer if the car idles well.

May i ask what the differences are? This is all so foreign to me.

 

[LeoP]

May i ask what the differences are? This is all so foreign to me.

Click on Dave Ray's link and it will probably explain the differences and why you should run manifold vacuum. Good luck!