Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Bill....I'm not sure that I understand the real point of your post here. Heard explained it rather clearly for you yesterday. And I'm not sure that you fully understand why the original road draft tubes were so large in diameter, vs the relatively small diameter of the tubing that PCV valves are plumbed-into. In fact, I'm beginning to wonder if you fully comprehend why pressure is created in the crankcase in the first place, and WHY there is such a necessity to relieve that pressure. I also have to wonder, since this article is so clearly labled "8BA", why you want to confuse matters referencing 'early' V8 oil pans with a 'draft' vent located at front....RIGHT? Same thing with reference to "not-sealed" rear mains on early V8s. We don't have this situation with an 8BA! And furthermore, you stated: "the accompanying pix shows the PCV system plumbed into the rear oil fill/breather tube". Well, the 'pix' DO NOT show that. The pics DO show the PCV valve & tubing ROUTED through that area, three to four inches below the breather tube itself, with the PCV valve being captured in a rubberized Dorman PCV valve holding fixture, which is part of a fully closed and sealed vacuum circuit (completely isolated from the fresh outside air supply). It's "plumbed" such that it makes way from the intake manifold vacuum source at a common plenum between the two carburetors, then entering the internals of the engine via a bulkhead fitting through the side of the 1" breather tube spacer. From that 90 degree fitting, the sealed circuit continues downward through the PCV valve (it's imperative to mount PCV valves vertically) and on to a compression fitting penetrating the now-capped-off exit tube which exits the oil pan chamber at the front of the valve chamber, and which ORIGINALLY connected to the original road draft tube. Check those pictures again! The pics below suggest ONLY the proximity of the PCV valve to the fresh air breather tube, which is now the avenue for injesting fresh air into the crankcase, and for adding lubricating oil.


https://www.fordbarn.com/forum/attac...2&d=1595568690


https://www.fordbarn.com/forum/attac...6&d=1595568399


https://www.fordbarn.com/forum/attac...7&d=1595568441


First of all, crankcase pressure is created as a result of blow-by, the relatively small volume of combustion gasses that travel past the piston rings and begin to pressurize the lower crankcase, as well as any other areas of the engine which are common/open to the lower pan area. That pressure needs to be relieved because if not relieved, gaskets will begin leaking oil or even be blown outward from their sealing surfaces. In some cases, oil can even be pressurized out of dip stick tubes. Unrelieved crankcase pressure has even been known to deform oil pans. BUT....it usually takes some span of time for pressure to increase to that point if NOT relieved. This pressurization is not huge in volume like combustion exhaust is. In that regard, crankcase pressurization is not an instantaneous process.


Normally, in stock configuration, and in the vintage engines we're discussing here, fresh air is allowed to enter through a usually-capped breather (and many times oil-fill) tube. Fresh air enters only at such times that contaminated crankcase air (let's call it blow-by) leaves the engine via the open, large diameter road draft tube which has been carefully engineered and plumbed down to a point near the road. That draft tube (aptly-named) was designed to be down there for a couple of reasons. First was so that all those pesky fumes and smoke end-up as far away as possible from the sight and smell of us humans riding in the vehicle. But secondly, the end of that large diameter tube was projected into the airstream under the car such that as the vehicle moved down the road, the air rushing past the open end of the tube produces a vacuum via the Bernoulli Principle, effectively sucking the fumes out of the crankcase, at a rate that surpasses the fumes escaping via pressure build-up alone. Relative to the diameter of the draft tube, there is not a huge volume of blow-by being produced in the first place, but the larger diameter of the road draft tube is required to take best advantage of the air passing by the opening at the bottom of the tube to create enough vacuum to be effective. There is not very much purging of the crankcase fumes going-on with the vehicle stopped while idling, as that is one time the PCV valve is least-open.

So Bill, when almost all automobiles began employing PCV systems, that large-diameter road-draft tube disappeared, right? And true, regulated vacuum (via the PCV valve) positively sucked the fumes out of the crankcase as well as relieving blow-by pressure, correct? The entire volume of blow-by passes through that small diameter tubing (usually 3/8" to 1/2" dia.), which also means that ALL of it must pass through the PCV valve. I don't believe I have ever seen an automotive PCV valve with an orifice any larger than about 3/8" diameter. Go out there and just look at that hose nipple on the vacuum fitting at the rear of the valley cover on your Y-block (like the red one below). Not very large, is it?


https://www.fordbarn.com/forum/attac...2&d=1597569164


You must remember that these engines produce a relatively small volume of blow-by (unless worn-out), that is easily evacuated when aided by the engine's manifold vacuum. You should also remember that dependent upon the level of vacuum being produced by the engine, the PCV valve is regulating it's volume of flow. Did you realize that a PCV valve is widest-open when the engine is producing the lowest level of vacuum?
Is there any other part of our dinky little PCV system here that I can attempt to further explain for you? We didn't go to the trouble of researching theory, doing some backyard-engineering, locating, procuring and documenting part numbers and supplies, nor take pictures and invest I don't know how much time laying this out and writing it up to tell everyone how it SHOULD be done. We only thought it might be kind'a cool to SHARE with others in a fairly concise manner, a plausible method which we devised to hide an ugly PCV valve, mounted in a vertical position, yet still affording the ability to service said valve without having to remove the intake for access. I don't believe I have it in me to make any of this any clearer. Promise....there was NO rocket science or gris-gris involved in this project. DD


…………….

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Well I've tried to send the pics bout three times now. Every time I get an error message! The only identification is Fenton and it is obviously for the 8BA series. I'll try again tomorrow. I guess the "ball" just keeps going out of bonds...

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Hey Bud.....Just e-mail a picture or two to me and I'll see if I can post 'em here for ya. Then, I'll have an idea of what to MAYBE suggest for your PCV valve. My e-mail below....please put something like "PCV Pictures" in the subject line. DD

[email protected]

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Well thank you DD and Heard for your excellent work here, super good info.

I have a scenario which I imagine could be quite common. I have found an Offenhauser 1079 4bbl intake which is for the early 32-48 Flatty, mine is a 1951 Flatty. As you see in the picture the 2 ports at the front are not drilled out, but are easily cut out to fit the road draft tube and oil fill/breather tube. My plan is to install the oil fill/breather and then drill/tap the road draft area to fit the PCV valve....and the million dollar question ($600,000 CDN) is...do you know a good PCV valve, similar to what you have chosen, that has a threaded base on it rather than utilizing a rubber grommet?

Appreciate any guidance you may offer.

Cheers

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

There are a few OE apps that had threads, but then you're stuck with whatever vacuum specifications those had.
M/E Wagner has an adjustable PCV valve.....

http://mewagner.com/

And an adapter you might be able to thread....
http://mewagner.com/?p=540

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Thanks! I found those adjustable units, very cool, but landed in Canada would be about $300:rolleyes:


I'll keep looking for a threaded unit.

Cheers

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Make sure you have the correct air flow direction. In other words, as an example, GM made at least two different threaded PCV valves and having threads is no indication of air flow direction. You need to determine which way you need the flow and which way the valve flows)

Non-exhaustive list....
2002 Mitsubishi Lancer

2002 Lexus

Hyundai, 1/8 pipe thread. P/N 26740-32804. (Fram P/N FV 266,
Universal with many apps including Chrysler, Kia, Mazda, Mitsubishi)

Datsun/Nissan (L/A/VG/U/R/CA/Z/E/J/GA) various 4 cylinder engines, British Standard Pipe threads

1965-69 Chevys (Camaro, Chevelle, Corvette)

Early 60's Ford truck 292’s are supposedly 3/8” threaded

1963 Ford Galaxie 352

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Thank you '48 F1, appreciate the info.

I just finished doing all my research as well and came up with similar results. I found Hyundai Sonata and Mits various engines and a number of other makes with engines from 2.5L up to 4L that use this one. Fram FV311 crosses to Beck Arnley 045-0270, threaded 1/8-28 BSPT, 1/8" pipe thread. And yes, will suck/blow on it to confirm if it threads into the manifold vacuum area, or the road tube section. I read someone's post where he put it in backwards and the vacuum sucked out the little brass insert and wiped out his $3200 350. Yikes!

Cheers

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

All good info. I am sure glad I don't have to be concerned about it though.

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

I think that Fram one you listed is the likely candidate.....

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

And that's the one I ordered...be here tomorrow and I'll let you know.


Thanks!

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Kilohertz .....Your positive critique is MUCHO appreciated. One thing to remember about PCV valves is that they are affected by engine displacement, and by expected vacuum levels. IF the camshaft you are planning on running is of any performance types, your vacuum levels will likely be diminished from a stock cam's vacuum levels. This is one reason to TRY to find a valve somewhat CLOSE to a match for your particular engine's characteristics. In our case, I believe Heard's engine is at 284 cu. in. displacement. I like the GM PCV valves because of the all metal, well-proven design. In our case, the only GM engines that I could think of even close in displacement, and with a performance cam was the '67-'69 Z-28s at 302 cu. in., and yup....they did have a rumpety-rump cam, for sure! That particular PCV valve is a Delco 19303069. IF running a stock cam, I'd source a PCV valve for a 283 Chevy engine, say 1965-ish.

Just about all of the PCV valves I've looked at which have a male threaded end are built such that the direction of flow through the valve is opposite of what you are trying to do, assuming that you want to drill and thread that blanked-off draft tube location. Those threaded ends usually thread into a vacuum port on a carburetor.

I might suggest carefully drilling a hole in that boss sized precisely for a rubber insert/grommet designed to receive a specific PCV valve. You'll want one similar to the one (in configuration) that we used in our project. The LARGE diameter end would fit down into the manifold, with the other end plumbed to a "MANIFOLD" vacuum source. REMEMBER...To run a set-up like this, the vertical tube must be in place at the front end of the valve chamber, underneath the manifold.
The Dorman web site shows a VERY extensive line of different PCV rubber grommets which your local parts store can order, if not in stock. These examples below can be seen at many sources on line. I know it's not what you wanted to hear, but you can still make the installation look tidy with just a little thought and planning. Hope this helps! DD

https://i.ebayimg.com/thumbs/images/...J5/s-l225.webp



........

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Thanks DD, great info, again.

I actually spent half the day doing research and looking and came up one which I have ordered and will be here tomorrow. It's threaded with a nice 1/8" NPT end which will thread right into the Offy manifold right under the carb, and 3/8" hose barb. There are 2 factory ports there, the other I will use for the manifold vacuum canister.

I found the one you mentioned for the chevy 283/327 but decided I wanted something for a smaller engine, mine is stock 239 (so far) and has about 17"Hg at idle. I'm hoping that will come up as the engine continues to run, and once I get to drive it a bit. The compression is quite low also at only 56-60 psi, again hoping driving it this summer will bring that back, if not, bore, Merc crank, shaved heads and start all over. :rolleyes: For now I thought I would experiment with the PCV, I cal always change it if it doesn't work correctly.

The one I chose is a Fram FV311, looks like this. It's used for a variety of engines from 3.0 - 4.0 L, I thought it would be close.

https://www.fordbarn.com/forum/data:...6hCTUIQhAf/9k=
https://www.fordbarn.com/forum/data:...6hCTUIQhAf/9k=
https://dpars.com/api/ImageHandler/G...ARS%2F58459996



I will drill/tap a hole in the road draft tube location for a corresponding right angle brass barb fitting like this.
https://images-na.ssl-images-amazon....1FEqA-1U-L.jpg
https://www.fordbarn.com/forum/data:...EREBERAREQf//Z
https://www.fordbarn.com/forum/data:...EREBERAREQf//Z

This should make for a neat looking PCV setup.


Thanks again for the help.


Cheers

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

That’s a great system !

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Thank you, and PLUS....it ain't ugly! DD

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Anyone have a solution for an Ardun?

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Coop/Heard, finished reading all of the post.
Thank you for a well defined way to use your system.
Thank you for sharing.
jim

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

I know this is a older post but I really like this system and am in the process of doing it to my 8BA with an Edelbrock Slingshot intake. I am changing it just a bit so I don't have to remove the custom oil fill tube and breather cap to check or replace the PVC valve. I made a piece to go into the spacer that holds the PVC valve. It may not be a clean as the other but works for me.

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Nice clean setup!

Re: PCV VALVE SYSTEM for 8BA with Early Intake Manifold
 

Man, I love watching a guy think really hard about how to approach a problem, and once he's figured a direction to go, just making parts work from scratch.....nice and neat, well-thought-out, and with slick workmanship. I LIKE what you've done there! And we really appreciate the feedback, too.

Coop

.