PCV system on 383 4bbl

-

Dave NEO

Well-Known Member
Joined
Jan 6, 2017
Messages
1,020
Reaction score
259
Location
midwest
mine on '68 barracuda has right side in place with connecting hose from carb to pcv valve on valve cover, but on the driver side the air cleaner is not attached with a hose to the oil filler cap (which is not the type with a nipple on it anyway). Does this matter at all; does it make any sense for one side to be in place without the other? It is supposed to be a closed system but if you are not concerned with legal issues/pollution, does this affect performance or anything else on way or the other. I'm liking the air cleaner nipple open to suck a bit more useful air. comments appreciated. thnx.
 
This is the way mine is hooked up.

IMG_1196.JPG
 
yea thanks I get it/know how it should go ..wondering if it matters much performance wise if you don't connect it all ..(see my post).
Very nice looking engine bay.
 
There are many threads here on the benefits of a correctly working PCV system. In short, make sure it's hooked up, the PCV valve as well as the breather.
 
mine on '68 barracuda has right side in place with connecting hose from carb to pcv valve on valve cover, but on the driver side the air cleaner is not attached with a hose to the oil filler cap (which is not the type with a nipple on it anyway). Does this matter at all; does it make any sense for one side to be in place without the other? It is supposed to be a closed system but if you are not concerned with legal issues/pollution, does this affect performance or anything else on way or the other. I'm liking the air cleaner nipple open to suck a bit more useful air. comments appreciated. thnx.

PCV is a bit of a performance killer actually, since it introduces oil mist and hydrocarbons into the intake air.
That said, it also has it's upsides like getting those acidic vapors out of your motor.
The biggest concern I see with yours is that you are not getting filtered air pulled into the motor. (unless I misunderstood)
 
At WOT
the system works backwards. Excess pressure goes up the pipe into the air filter house. No pipe? then it spews all over everything in sight,lol. If you put a breather on there it will catch most of it
 
well AJ that is where I thought we might be heading...for Trailbeast, the air from the air cleaner housing to the oil cap via the hose is not filtered air - it just enters the hose from under the air cleaner housing - however in a reverse flow situation, I can see where the air going from the oil filler cap back to the air cleaner housing will end up getting filtered as it gets sucked through air filter into carb. So that makes sense AJ sir. My oil filler cap is vented and allows air to enter though it to the crankcase, creating a flow through to the opposite side and the PCV I suppose. The filter in the oil cap should catch any crap that might 'spew' in a reverse flow scenario in WOT should that happen. The unused nipple on the air cleaner housing just lets some additional air into the carb. I attached a hose to this nipple and ran it to the grille with a funnel on the end to get he benefit of some cold rushing air into the air cleaner albeit a pretty small amount..can't hurt. OK call it HILLBILLY RAM AIR!
101_3289 (1).JPG
101_3290.JPG
 
Dude you want every 1/64 of a hp you can get. Ditch the PCV system. Road draft tube it & call it a day! :thumbsup: You do relize I'm pulling your chain?
 
haven't dnyo'd it yet but will keep you posted..:steering:

seriously, was simply wondering if I needed to connect the left side of system for a good reason and I think you guys answered that so thanks. I see now that the right side with PCV still feeds into bottom of carb as factory intended so hopefully with a clean/functioning PC valve it does not crud up the carb..much.
 
Last edited:
Early systems never were hooked to the air cleaner...they just drew air through the breather cap, which had "some" filtering media inside (to stop the boulders).

20150625 062.jpg
 
I was there in the early '60's as smog laws were changing. Frustrating time for mechanics as this was impacting used cars as well. Just to clarify- the presence of a hose from the a/c to the valve cover breather makes this a "closed system". Previous models were vented to the atmosphere, leading to some oil misting on valve cover. The purpose of the "closed" system was a "smog" requirement preventing crankcase gasses from escaping into the atmosphere. Performance? If you have a 10-sec car or better, you might consider eliminating the PVC system.
 
I can tell you my oil breather cap has never been attached to the air cleaner and does not blow anything anywhere. It has a wire mesh filter inside it though, maybe some don't.
 
Remember, my observations are from a California perspective. During the '60's, California was more "progressive", (stupid ?), than some. This is why there are some differences in cars from other states. During these years, some shops were quiting smog certifications because the laws seemed to be changing daily. My car= 1968 cuda BB, who remembers the CAP valve? My car still wears one. Wasn't this a California thing? They had either a green cap or a black cap. Their purpose was to retard the vacuum signal to the vacuum advance during deceleration. More smog crap. Since mine is a restoration, it will continue to have one. They can be adjusted to non-op.
 
Just to clarify- the presence of a hose from the a/c to the valve cover breather makes this a "closed system"

Sorta. Look at the picture in post #2. Those type breathers on that driver's side valve cover are open on the bottom side. Though that is technically called a closed PCV system, it's really not. Now, if that was one of the valve cover breathers from about 1971, it would be completely closed and have another tube with a hose that went to the charcoal canister......I believe. There was a second tube that went "somewhere", but the breather was closed.
 
My California car has closed system as in post #2, but that chrome breather has no holes on the bottom, it is sealed, it is "closed". Here is a blast from the past- the CAP valve. Remember?
100_2349.JPG
100_2350.JPG
 
It's always fun to share idea's with you guys even if we don't quite agree. We should have a big BBQ where we could meet and share our lies and fractured memories.
 
-
Back
Top