Breather Cap Question

[Turbo4whl]

One more thing..... Do I need to run anything from the Manifold Vacuum Port?

If the brake booster gets vacuum from the base of the carb. and not the vacuum port on the manifold, that is good. Do you have an automatic transmission? That needs two vacuum sources.

I don't see air conditioning, that also would need vacuum.

The charcoal canister needs vacuum but the truck may have that removed or disconnected.

 

[Rusty Nail]

Is there anything that I should hook up to the remaining port to the right?

Not likely. Bruce hints at options however.
Temp sensor and air cleaner, ignition advance are all possibilities.
MAP sensor?
BARO?
EFE?

Ain't broke I wouldn't fix it.

*UNSOLICITED ADVICE*
Move more slowly and make one change at a time - to allow plenty of time to observe the effects , could be good advice. Certain changes require many key starts and completed cooling cycles to take hold yet forever remain fluid.
Remember all of those parts are 37 years old and likely set in their ways. I proceed with great care.

 

[Octane]

Is there anything that I should hook up to the remaining port to the right?

My advance is plugged into the port on the right.Its my factory hookup.I have a quadrajet 4mv

 

[82sbshortbed]

I had 2 breathers like you. But, after asking about the advantages of a pcv valve I put one in on right valve cover and hooked up hose to big port on bottom front of carb. Hope this helps.

You must be registered for see images attach

 

[Rusty Nail]

That's a Dodge?! ^

 

[Turbo4whl]

That's a Dodge?! ^

Rusty you are funny! Have you been thinking about so many LS engines you forgot what a real Rat engine looks like?

@82sbshortbed
Doug, no heater in that truck? I thought it gets cold in Texas every now and then.

 

[82sbshortbed]

Yesir it sure did!

 

[Moose Drool]

If the brake booster gets vacuum from the base of the carb. and not the vacuum port on the manifold, that is good. Do you have an automatic transmission? That needs two vacuum sources.

I don't see air conditioning, that also would need vacuum.

The charcoal canister needs vacuum but the truck may have that removed or disconnected.

Manual transmission, no air conditioning.

 

[75gmck25]

A stock Quadrajet or the typical Edelbrock 1406 usually has at least four vacuum ports - (1) large threaded port on the back that has a metal tube attached, used for vacuum to the brake booster, (2) 3/8” port nipple on the front center, used for PCV, (3) small full vacuum port on front, and (4) small ported vacuum port on the front. 3 or 4 are usually used to connect the distributor vacuum advance.
In a addition, there is a threaded vacuum port on the back of the intake manifold, usually toward the passenger side, and it will have a vacuum tree attached. On my truck that is where the HVAC and other vacuum accessories are connected.

There is a fairly long list of possible vacuum accessories, in addition to the brake booster, PCV and vacuum advance I listed above. The most common I’ve seen are the HVAC controls, the cold air door in the air cleaner, the fuel vapor recovery canister, and the cruise control. Depending on emissions controls, there may be vacuum connected to several additional items.

Bruce

 

[Raider L]

There may be a grommet that will fit in the back hole on the cover, passenger side, for a PCV. Otherwise, You may have to find a valve cover that has the PCV hole in it. Or you can block off that breather hole in the back and drill a hole in the cover and put a PCV grommet in that. Also, depending on what compression your engine is, you may not require a breather at all. My engine has 9.2:1 and I don't need a breather at all. I have a old style rubber cap where I put oil in the valve cover. Also to, cam overlap has to do with excess crankcase pressure buildup and need to vent. So, unless you have a more than stock to mild performance engine you don't need a vented cap. It may also have to do with oil hanging in the top of the heads as well causing some amount of excess oil use.

 

[Raider L]

396 engines didn't have a breather cap. It just had a cap that didn't allow any breathing, maybe only slightly, and was a place to put the oil in.

 

[Bextreme04]

396 engines didn't have a breather cap. It just had a cap that didn't allow any breathing, maybe only slightly, and was a place to put the oil in.

What 396 didn't have a breather of any kind? Late 60's-70's 396's used a PCV and breather into the air filter box. Early 60's 396's had some weird stuff, but always had some kind of breather system AFAIK. The 65 Corvette 396 had a breather into the air cleaner on one valve cover and a hard pipe with a fixed orifice from the drivers side valve cover into a manifold vacuum port source on the carburetor. You were apparently supposed to remove and clean that pipe every 12,000 miles. I'll post a link to a forum post with some pretty pics and good info since its on a non-competing forum.
https://www.corvetteforum.com/forums/c1-and-c2-corvettes/4283353-1965-vent-routing-396-a.html

 

[Octane]

There was a metal pipe running from valve cover to breather housing and connecting to a small filter inside. And a pcv on one valve cover. I still have that system on my truck.Lots of people done away with it and just put a breather cap on valve cover,and of course leaving the pcv hooked up as is.

 

[Raider L]

Yeah, I forgot about all those little hoses and pipes and stuff like that. I was thinking on the valve covers like he's got on there. Remember the crinkly looking silver hose that had one end on the air cleaner snorkle that went to a pipe off the exhaust manifold? It put hot air mixed with outside air for cold starting. I had one of those on my truck when i got it. I ripped that thing off when it kept falling off and you never could get the thing back on tight. I threw it in the trash. Yeah, the air cleaner had all kinds of doors and filters, little hoses, cannisters and that was just the '70's, wait 'till the '80's you couldn't even find the engine for hoses and pipes! If you guys want to call that "breathers", okay. I call all that crap EPA garbage!

 

[Raider L]

@Bextreme04,

I looked at the site. Just EPA garbage. Does it improve performance? Nope. Did it up HP? Nope. So what did or does it do ? It cleans up the air and makes the unicorns hop higher and the rainbow clouds prettier! Throw that crap in the garbage where it belongs!