19doug90

the only problem i see with that is what if all of the oil doesnt burn then youll end up spitting crap out of the exhaust and i dont know how preferable that is to having crud in your intake.

lykan

Think about how long it would take to build up in the hot exhaust versus the cool intake.

People go 100k miles before they clean out their intake. I can't imagine the exhaust getting any worse in a shorter period of time.

strokedtpi

on the passengers side of my car there is no pvc...and at the moment i have no vacuum coming from the throttle body port where the line connects(possible oil build up i dunno....) but would it be okay then to run a breather just on one side>??

B4Ctom1

If you do it on a N/A car then you are probably ok but on a power adder car oil mist can contaminate the intake charge from blowby.

not if you have smog checks

strokedtpi

no smog checks here...whatya think

25THRSS

you will be fine.

joshwilson3

.

Nozzghoull

Geez! Maybe I don't know what the hell I'm doing but I'm running dual breathers on my stroker (carbed) and everthing is sweet! The only problem is the fumes are strong under the hood. They don't drip, leak or blow crap on my engine and if they did I would replace them with something else because the majority of my parts are polished aluminum and too expensive to let them get screwed up by a bunch of gunk. No build up anywhere either, so far. Everyone has stated some pretty good points but it seems it's just pretty much a matter of opinion. I haven't seen any evidence that one way or the other will ruin anything, other than the ozone!

JakeJr

There are a couple of tricks.

First, some amount of air always gets past the rings as the engine is running. The higher the RPM, the more. Something has to be done to address the build up of crankcase pressure - something to vent it - or the pressure will unload the rings and/or blow out the gasket(s).

So you need to either have a functional PCV system or one of the other fixes for the problem. Racers use a hose attached to the headers from the valve covers to vent the crankcase. The latest version involves installed a high dollar vacuum pump setup.

Some guys just plumb their valve covers for push/screw in breathers and dump the PCV altogether.

To run a stock type PCV setup you can add filters inline which will trap the oil mist the accumulates. If placed right on top of the valve cover, gravity will let it drain back in. These will need to be changed periodically though, how often depends on how tight the engine is.

Some guys install fuel filters in the PVC hose to trap the oil mist. They allow vacuum through, but not the oil that accumulates.

I just finished building a 434 for a friend's 86 Vette and we went with two breathers per valve cover. If, at 7000 RPM, we still have a blow-by problem with all the oil that will be getting whipped around, we'll have to go the vacuum pump route.

Just my thoughts; hope this helps.

Jake

MrDude_1

mmk, ive been researching this all day...


1. the system has 2 purposes... to remove the gunk in the motor, and to remove pressure.

2. vents only remove pressure, but NOT the buildup.

3. you guys are trying to use fuel filters as oil seperatiors..... while the only oil seperators ive found so far are for airplanes (so they can fly upside down) im sure SOMEONE has one cheap for non avation use...

im currently looking for a oil seperator now... that way, any oil build up in my catch can can automaticly return to the pan.... and i can run a badass vac pump on the street with zero mainentce... thats my concept atleast.




remember... 2 goals of the system.... one is pressure, other is to remove the vapors..

you need fresh airflow to do this.

JakeJr

We went with the very tall stand-offs to mount the breathers to help prevent that from happening.

I've seen a buddy's 1/8th mile car come back from a pass with both his breathers blown off. Fresh engine too. Lots of pressure to deal with, effectively.

Ever check out a Winston Cup engine to see how those boys vent their stuff? Up 9000+ RPMs for 500 miles sure whips around a lot of air/oil.

Jake

MrDude_1

im pretty sure they use a vac pump.... and that they have a dry stump system..


athough thats only a guess from the fact that they have the oil tank in the car........

25THRSS

yeap, they do have a dry sump, but i'm not exactly sure how they vent the crankcase.

SSC

The filter works fine just remember I thought of it 1st, years ago. Doh should have pattend the idea changed some lables around and sold it for 3 times the amount. You can run without a PCV valve but to vent properly you would need a vent tube in the oil pan like old AMC's and HD GM trucks. I dont think a 1in vent tube would look to snazzy running up past my headers.

Also the amount of vacuum required by the PVC is different engine to engine. Some 2.8's for example would have to much vacuum into the engine and the dealer trick was to restrict the sucktion by inserting a plastic valve stem cap with the nipple choped off into the line. It works on low vacuum V8's as well.

89BlueIROCZ28

the gasses that can build up in the crankcase are acidic which is very detrimental to the engine. Just something to think about!

JakeJr

Dennis Wells said that he's seen the oil pans of engines running on his engine dyno actually BALLOON from the pressure when the engine wasn't sufficiently vented.

You can only imagine how long the gasket seals will last.

Food for thought.
Jake

MrDude_1

there you are again thinkin about pressure





pressure isnt even the issue... thats the 2ndary thing you have to watch for on a street motor.





think what you quoted...... you want that bad **** out of the motor.....



i repeat... it has 2 functions

remove the bad gases
relieve pressure.


TWO. not just one.

breathers only solve one.



ok solution for race motor.


bad solution for street car.

JakeJr

Some of us older guys can remember when engines came from the factory with no PCV system at all. Then along comes emission concerns and the PCV system was invented.

To my thinking, venting the engine with breathers is the best, least costly way since the "bad" air is not reintroduced into the engine to be mixed with fresh air/fuel, thus diluting it.

The main concern with breathers, for me, is that many valve covers do not have oil seperators on the underside of the covers, so oil gets splashed up into the breather, eventually flooding the filter medium and resulting in oil all over the engine compartment.

Stud girldles, roller rockers and reduced clearances inside the engine compartment all contribute to the requirement to delete the seperators, and I guess it does save the maker a few cents too.

Some breathers are designed to allow the accumulated oil to drain back into the head, via gravity.

And most don't come with drippers anymore either. When I added roller rockers to my engine I had to grind off the factory drippers to get the clearance I needed.

And, yes, you have the issue with fumes when running breathers, too.

Jake

25THRSS

If they didn't remove the "bad gasses" then why do people complain about the smell after they put breathers on? I'll tell you, because they do. Anyone ever think about how the pcv works on vaccuum and at WOT, there should be no vaccuum, so breathers would be better at WOT to vent the crankcase pressure. Like said before, there really isn't a downside to removing the pcv, except for the possibility of oil getting on your valve covers and the smell. Other than that, I like it because you don't get that crap getting sucked back into your engine.

85TransAm406

iTrader: (1)

I just think the PCV was the evolution of the standard 2 breather setup, with the POSITIVE part of positive crankcase ventilation being the evolution part. On almost any given automotive system, there is almost always room 4 improvement, isn't that what we do to our cars now? Anyway, out of that 750 CFM of air that your car draws in, do you think that 20 CFM from the PCV system is really gonna hurt?

OMINOUS_87

Under casual driving PCV gases wont have a huge impact on performance. Under WOT however lies a question, how much vaccum does an engine make, and how much will actually be flowing through the PCV system?

Well beyond the gases debate, the only thing that could hurt performance is the oil buildup, if the gases are not filtered the oil will find its way to the combustion process where it will potentaily cause or contribute to detonation.

I have come away from this quest with a PCV system that employs a large catch can packed with steel wool, so oil free air is delivered to the combustion process.

I ditched the idea of breathers, a bit antiquated compared to PCV.

stuart69427

At WOT vacuum would be almost nill if not nill, correct? So without vacuum being implied to the PCV Valve there won't be any PCV gases/pressure vented into the intake, right?

Wouldn't WOT be the most critical point in which to vent this pressure/gases becuase blow-by would be at its peak??? This is how I see it at least.

So yes, in this respect I see how the PCV system could be improved.

What about emmissions that is the whole point their vented into the intake, to be given a second chance to burn

OMINOUS_87

You got it, at WOT there should be no vaccum in the intake.

MrDude_1

umm

its smells because the gas wafts out and around the engine compartment when you park it.



i said it wasnt as effective and that it didnt force the gasses out...

of course some gets out. its not like its a all or nothing deal


like someone else said....."evolution of the standard 2 breather setup"


good way to put that.




other then getting your intake "all oily" tell me a reason not to run it.


if you're that **** about the oil, get a air/oil seperater and use that between the intake and PCV



at WOT, there may be no vac, but any pressure inside will go out thru both the PCV and the breather/air inlet.

as soon as you let out of WOT, it starts working again... this is why its a street car setup.... drag cars just run down the strip and thats it... so its a non issue for them.

long term WOT race cars run a vac pump..

MrDude_1

on a side note:

eventually i would like to run in one of thoes long tern high speed races... like the silver state classic.......


thats why, if you read my other thread, eventually id like to get a vac pump

25THRSS

You got it, but the whole point of removing the pcv is so it isn't vented back into the engine. I am not a tree hugger, lol.

85TransAm406

iTrader: (1)

The whole point isn't emissions, it's crankcase ventilation, removing "bad gasses" that can contain a number of vaporized contaminants. It's not "vented" into the intake, that's just the vacuum source, and since the contaminants are already vaporized, they will most likely exit through the exhaust the 2nd time around (some will still burn further). And at WOT, crankcase pressure is increased, lessening the need for the vacuum, so the gasses are still pushed out into the PCV system to be evacuated.

85TransAm406

iTrader: (1)

BTW, that was just basically a summary of what i remember from my gasoline engines class (mechanical engineering).

25THRSS

The pcv system was infact invented for emmisions reasons, and how the hell isn't it vented into the intake if it's getting sucked back into it? Also, how much gasses can actually be pushed through that tiny space around the ball inside the valve? Not enough if you ask me.

85TransAm406

iTrader: (1)

When i said vented, i meant lack of a pressure differential on one side of the PCV valve, creating either a vacuum effect or push effect. I never said the PCV system wasn't used as an emissions control device, just not the primary purpose.

Here's a quote from hastings filter engineering section of their website.

A neglected PCV system will soon fail to function and the result can be expensive as well as troublesome for the car owner. If the crankcase is not adequately ventilated, the motor oil will quickly become contaminated and heavy sludge accumulations will begin to form. Internal parts, not protected by the motor oil, will begin to rust and/or corrode due to the water and acids that will become trapped within the crankcase. If the PCV system is not functioning properly, the flow of crankcase vapor into the intake manifold will not be properly metered. This, in turn, will upset the fuel/air mixture for combustion and cause rough idling or even stalling of the engine. Furthermore, intake and exhaust valves, in addition to spark plugs, may well be burned and rendered useless, prematurely affecting performance and requiring expensive repairs. To assure trouble-free performance of the PCV system and, in turn, the engine and vehicle, routine maintenance of the PCV system is absolutely recommended and required.


And here's the entire link to their PCV explanation:
http://www.hastingsfilter.com/engine...tsb_94-2r.html
here's a link on building a oil catch canister:
http://www.allpar.com/fix/pcv-breather.html

IRACE87

PCV and gapless ring = lots of oil in the intake.
http://web.camaross.com/forums/showt...hreadid=218309

PAT

Trans_AM_88

Aren’t the "gases" in the crank case (from blow-by) basically just exhaust fumes? We don’t see headers (or header gaskets, for that matter) being destroyed by these fumes...and if these fumes are so toxic to pan seals and such, then how does the PVC hose last for tens of thousands of miles?


Also, I still don't quite understand what has been said in this thread over and over again...how does a PVC system vent "clean" air into the crank case? Everything that the PVC takes out of the valve covers gets pumped right back into the intake, which in turn is just combusted again and ending up back in the crank case, right? So we're basically just back where we started with fumes in the crank case. Furthermore, there can’t be a positive effect of putting exhaust fumes in the intake can there? Oh wait there would be, emissions . This would support the fact that the PVC system was created to keep those crank case fumes in circulation, and not releasing them into the atmosphere.

Just my .02

Red Devil

T/A 88, the other hose that runs to the other rocker cover allows fresh air into the motor.

You guys seem to miss the point. Yes it's emissions, so the volatiles won't just waft into the air, but just like penicillin, there was an unexpected plus side. The beginning of the 200,000+ mi engine. Ask any of the guys that were around in the days of the breathers. How many cars did you see living well past 100K without a rebuild? The crap left in your motor is, as previously mentioned, acidic. How well do bearings last in that environment? There is a slew of other reasons, but I'm lazy.

Also, the vacuum pumps do more than just vent the crankcase, they create negative pressure in order to create a better ring seal.

joshwilson3

.

MrDude_1

well the increased crankcase pressure will still force it into the intake at WOT.

yes. and thats also the reason for vacuume pumps on race motors. but this is on the street, so you need a low maintenance, reliable system. the PCV valve does that.
this is about engine life, and not covering the motor with oil (fire hazard)
if you're not even going to get 20k out of your "street" motor, and you clean it after it mists some oil on it, dont worry about PCV..
if you drive on the street nearly as much as i do, then you need it.

side issue.
just because it may effect emissions, doesnt mean that its a "bad evil power robbing thing"... not to mention, i dont think it helps at all...
i mean, you're burning a small amount of oil. small enough to not effect power output at all. but any oil in the system wont burn completly.. and that has to have atleast some negitive effect on emissions


it sucks clean filtered air from outside... in some OEM cases its the air cleaner, in others, its a seperate filter.
the air is drawn or pushed (however you want to look at it) into the intake...
so the crankcase is vented from the atmosphere, to the intake...
and like i said, i dont think it helps emissions.... unless you're counting possibly spraying a oil mist in the air from regular breathers...

start your car.
pull the PCV valve off
stick your finger over it.

pulls pretty damn hard huh?


QUOTE]Originally posted by Trans_AM_88
Aren’t the "gases" in the crank case (from blow-by) basically just exhaust fumes? We don’t see headers (or header gaskets, for that matter) being destroyed by these fumes...and if these fumes are so toxic to pan seals and such, then how does the PVC hose last for tens of thousands of miles?
[/QUOTE]

simple. if you stored some headers in a jar with the gas in it, they would corrode faster then the same header in the atmosphere. but generally, its blown out the header.. it doesnt have a chance to condense and stay on there like it can in a semi-enclosed space like the crankcase.
and PCV hose only lasts that long because its made for it. it is a special rubber that isnt effected by gas, oil, and some other chemicals. take a regular rubber hose, and it will deterorate in a matter of months.. a year max.

you're obviously a lil confused about the system, so i'll break it down for ya.


it sucks in clean, fresh filtered air from the atmosphere. a filtered breather on the pass side valve cover, or in the case of TBI, theres a 2nd filter just for it inside the air cleaner cover... note that this isnt in the intake manifold.. this is above the throttlebody.. nice filtered clean air.. no combustion by-products or anything.

this nice clean air is pulled thru the pass side head into the crankcase, across the motor, back up to the drivers side head, and from there its pulled thru the PCV valve and into the motor.
because of the nice even and mostly constant flow of the system, you can also see how its mostly fresh, clean air... with just some contamination in it...

its not like the engine is breathing exhaust... or anything else bad.
its just some air with some acidic gases in it. now if thoes gases remain in the motor, they condense... then you have some acid eating away at your bearings... get it?

note, this doesnt take power away from anything... you could be on a dyno with a throttle stop doing accuate part throttle (so theres still vac) runs... and they would remain the same... the error of the dyno would be a bigger variable then the PCV system.

umm... no.

see you arnt putting exhaust into the motor. you're putting clean air with some acidic gas in. with a light oil mist possibly.

it was created to get thoes crankcase fumes OUT. not keep them in circulation.
in the 50s and early 60s, when the SBC was new, the only crankcase vent was a hole in the back of the block.. and later, a breather on a tube on the intake.
did it work? yes.
did their engines last nearly as long? no.
it is a simple, effective system. the only downside being a light oil mist on the intake.
after 12-20 years (depending on the 3rdgen) look at the inside of your intake.
you see that light build up?
that took over 12 years to make (on a 92!)
and its mostly superficial!! it just LOOKS dirty...so dont worry about it.


well... it could be a nice place for the gas to condense and then drain back into the motor... but i suppose as long as you set it so it cant drain back in, and regularly changed it, it wouldnt hurt anything...

but like i said, its just looks.. and it took over a decade to even look that way.

RB83L69

Bottom line: if you drive it on the street, use it. It is a good thing.

It was "invented" for "emissions purposes", but only in the sense that it does a better job than the thing it replaced, and lowers emissions at the same time. What it replaced was the old "road draft" tubes that just sort of led from a convenient hole in the crankcase to some point under the car with low air pressure when the car was in motion.

You pretty much gotta have some kind of vent. You might as well use one that doesn't spew oil mist and misc other funk all over your engine, and that keeps your oil clean at the same time. There's no down side to using a proper PCV system, on a street car. Frankly I can't see whot there is to argue; we might as well argue about whether the earth is flat. Arguing about the PCV system won't change the fact that it's beneficial, just like arguing about the shape of the earth won't change that either.

In point of fact, if you have a properly sealed engine, you can put your finger over the clean air intake hose (the one that comes off the air cleaner), and if you wait a few seconds, you can feel the vacuum building up in the crankcase and hear the air rushing in to replace what was sucked out through the PCV valve while you had the intake hose blocked.

Meatikis

i think that this idea is a good solution but wouldn't it allow for a little leaking? also what would be the difference from this

Meatikis

and this...

Meatikis

oops forgot to attach the image

MrDude_1

the only diff im seeing between the two is one uses a breather on a tank, and the other is just a breather.


if thats it, then the only diff is slightly less oil mess coming from the breather.... really, id do teh 2nd one, just to save $ and space.

B4Ctom1

The reason my original drawing there uses the moroso or jaz filter catch can instead of just a filter in the valve cover is because under nitrous or boost alot of engines experience blowby or exhausted oil mist from the crank case, and if you are smoking down the track and the tech guy follows you to the pit and sees the oil all over you wont get back on the track. thats why I proposed the dual can system. We installed it on a stang with a D-1 and it works like a charm. Im going to duplicate my design on my 91 Z with the cranked up P-1sc.

Meatikis

Ooooohh.. that makes sense. yeah those tech guys really dont like it when people spill fluids on the lanes....can't imagine why...

B4Ctom1

yes and under boost unless you have a vacuum crank case system with a pump to keep a steady source of vacuum in the crank case that can out speed and out power the blowby forces you will need to consider the dual catch cans. since you lose your pcv type vacuum under boost or under WOT period you need to use the catch cans for when there is no vacuum to sem the tide of full power blowby. you have to keep the catch cans empty or check them often etc. there will always be a tiny bit of il in there but you need to not forget about them.

Meatikis

what happens if they fill????

MrDude_1

think about it.

the can holds about a quart of oil.



i have a fully functioning PCV system.
i have over 124,000 miles on my motor.

i use less the 1/4 of a quart of oil between oil changes.


if you're losing a quart of oil and know it, you should already be checking the oil level regularly. otherwise, you could wait between oil changes.



but id imagine most people who go thru the work and money to put a supercharger or any other kind of boost device on their motor would atleast check the oil.... and just empty the cans when you do.

it would be trick to have a auto return, but a lil overkill...

B4Ctom1

well it might take a few seasons to fill them, but I wouldnt try to push it, check early, check often

Vader

You're really over-complicating it. Why not simply install an auto drain breather?

1983Fbody

Okay, how does this sound for a setup, two breathers in the back with a balance tube connecting them and two pcv valves in the front connected with a T fitting, then plugged into the carb (vacume source)? I'd need valve covers with four holes and two oil baffles or fab some up. Would this setup add any hp?

Vader

You think this will help:

https://www.thirdgen.org/techbb2/sho...hreadid=134224

...or do I need to get part numbers, photos, descriptions and accounts, and write antother tech article?

Randel '86

poor 25THRSS took like 50 attempts to get his question awnsered. Anyway, I was thiking. If you blow on the end of a straw, across it, you create a vacuum inside, much like how a paint can sprays actually. Now I realize this is useless when you are sitting still, but maybe running your pcv lines down to somewhere that will get some air when you are moving. And pointing them straight down at the ground, would create enough vacuum to actually pull as much, or more, as the intake would. (I can pump out a whole lotta water by me just blowing on the straw, just think what 30, 50, or even 70 mph would do?)