Alright fellers...manifold question

[BIG RENO AL]

I have recently acquired an new exhaust manifold for my '72 fj40 from delancy (thanks Pal!) and have noticed a difference between the new and the old. My old one has a vacuum port on it and the newly acquired on does not. Is this an important difference or should I just disregard?

 

[shelfboy1]

are you using it now ?if there is another hole not being used you can run a longer line but i think that goes to the emissions box or tube type on the fender, depends on weather its hooked up or not.drilling and tapping the manifold is not a big deal if you need it .more info and a photo of what its hooked may get a better answer good luck

 

[edwjmcgrath]

Funny looking exhaust manifold.

 

[tucker74]

Will be fine, you can pull vacuum from somewhere else if needed . There were a lot of different configurations in the '70s to try and meet rapidly changing emissions rules, there were even different vehicles sold in different parts of the country to meet local laws.

Tucker

 

[Copenhagen1]

Big Al that looks like an intake manifold to me. An exhaust manifold definitely would not have a vacuum fitting.

Since your truck is a 1972, I don't think you have to pass emission tests anywhere but I might be wrong.

Outside of a state requirement, you really don't need that vacuum fitting as long as you can get vacuum somewhere else for whatever that is supplying vacuum to.

Not sure if that answer is clear or not.

Sent from my iPhone using IH8MUD

 

[edwjmcgrath]

72 should have 5 hoses going into the VSV (vacuum switching valve).

1) To diaphragm on the back side of carburetor.
2) To ported vacuum port on carburetor base plate.
3) To hex shaped fitting on intake manifold
4) To Distributor vacuum advance.
5) To steel line that runs along top of firewall then to the forward one of the 2 ports on the top of the evap canister mounted low on the passenger side of the engine compartment.

If it was my truck, I would run a vacuum line directly from 2 to 4 so that you get ported vacuum to the
distributor. The other lines are for smog and will not affect your operation. The carb diaphragm is a smog feature that keeps the throttle open in certain situations. The vac line will also suck fuel vapors from the charcoal canister. As long as there is no vacuum line, you don't need to worry about capping off any of the hoses.