yippee!! i've got secondaries!

[brent vendsel]

i just changed out my 2 bbl for a carter 650 (thanx rumblefish 360-works great!).does anybody know what the large vacuum port (1\2")on the top by the fuel inlet is for? i think the one in the front at the base of the carb is for pcv, right?thanx in advance for any replies.

[Doug Wilson]

Is this an old carb?

[brent vendsel]

i'm not sure of the year, doug. it's not an edelbrock, and it has an electric choke.

[Doug Wilson]

Does the carb have the vacuum-type secondaries, like the recent Edelbrocks and Carters? Also, how many ports does it have in total?

[brent vendsel]

yeah, there's a weighted flapper inside the secondary bores. it has 2 big ports,1 in the front on the bottom by the idle screws, 1 on the fuel inlet side that that comes out under the air filter, and two small ones also in the front.oh yeah, there is also a large one in the back at the bottom, but it is plugged . and there is one off the side of the choke.(small)

[charger_dan]

My AFB had one of these. It's a fuel bowl vent tube.
There's no vacuum present at this point.
It simply vents fuel vapors to the outside atmosphere.

Typically, rubber line plumbs from this nipple up to the
underside of the air cleaner, allowing fuel bowl vapors
to recycle back into the intake charge for combustion.

Don't want to deal with it? Don't worry about it.

Going from 2 to 4 barrels is kinda like a coming of age,
sorta like that first kiss or your driver's license...heheh

[rumblefish360]

Hey Brent;

That is a Carter 625 cfm emmissions carb. The vent as described above was to be hooked up to the stock charcoal canister. Do not plug it, run it open and do not worry about it. The pluged unit in the rear is for vaccum.
Your correct about the PVC being up front.
The "weighted flapper inside the secondary bores" is called an Air velocity valve"
Any more questions, just post, we'll all here for ya.

(thanx rumblefish 360-works great!)

No no, thank you. And I knew you would like it.

[brent vendsel]

i plugged 'em all yesterday, so i could get it running(it was getting dark and cold!).i took the hose off today and put my thumb over it while running, you're right, no vacuum! i set my timing and idle mix at work today and the black smoke is gone!
the carb works great, now i just need some more cubes!