Timothayyy

iTrader: (2)

I got a few of them.

1. My friend says they spit oil and that a catch can is a lot better. Do they spit? Are catch cans better?

2. I read on here that the drivers side valve cover needs the PCV valve so that it can maintain vacuum. Is that true? Can I only have a breather on the passenger side?

3. The black metal tube that goes from the passenger side valve cover to the intake, do I need that? Like do I only need it if i have a PCV valve, or do i need it regardless?

Yes ive looked through the Haynes manual, it only says the PCV is there to lower emissions. I dident see anything about vacuum.

Thanks, Tim

Lo-tec

The pcv system sucks air into the engine crankcase through the pass side valvecover (black metal tube) and then goes through the pcv valve on the drivers side valve cover and into the carb where the vapor is burned. I would leave the system on, and if you want to you can put a breather on the pass. side valve cover in place of the black metal tube.

Air_Adam

Keep the PCV valve. It doesn't matter which valve cover its in, as long as its in one of them.

The PCV valve does sorta help lower emitions, but it also sucks bad vapors out of the crankcase that can turn the engine oil acidic, and it helps to keep the oil cleaner longer. It also helps piston ring seal. It also helps to prevent oil leaks at gaskets because it maintains a bit of a negative pressure inside the engine, keeping fluids from seeping out.

Breather caps will just vent the engine fumes out of them, so they do make a big mess all over everything, because its just nasty oil vapor floating around under the hood. They also don't help ring seal or old gaskets, so you may find your engine starting to leak or burn oil if you remove the PCV valve.

The tube going to your intake from the valve cover on the opposite valve cover to the PCV valve is just a vent - its just taking in fresh air to replace what the PCV valve sucks out. You could replace it with a breather cap, like you'd have to with an aftermarket air cleaner, but if the tube already fits up like its supposed to, theres no reason you remove it. Either way, it has to be filtered air. If you look inside the air cleaner where the tube hooks up, there should be a little fluffy looking pad on the inside of where the tube hooks up - thats a little air filter for it. A breather cap has a similar filter inside its cap.

Timothayyy

iTrader: (2)

Alright thanks.

Now I ask if I can have a breather and PCV on the same valve cover?
Reason I ask is because one of my valve covers has 2 holes on it, the other has just 1.
If I can have 1 breather on the valve cover with the single hole, and then the breather AND PCV valve on the other that would be easier then finding something else to plug up the hole.

Apeiron

Not if you expect it to work.
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Try an oil filler cap.

Timothayyy

iTrader: (2)

Good call on the oil filler cap, thanks for answering my questions.

Wishmaster's87IROC

iTrader: (4)

hmm? well ive been running a breather on both side along with my PVC that connects under the plenum and dont notice a difference..surely not in performance...I dont think?

a friend of mine with an EFI mustang told me that I dont need a PVC system cause he used to hav it on his and got alot of crankcase pressure and when he put breathers on it relieved it and stopped the leaks he was gettin..

thats why I ask..

Im trying to do the same thing, Ive got a leak between the pan and the gasket right under the rear main...I know i'll just have to remove the motor again JUST to FIX that...and I dont want to...but I know its the only way.

Apeiron

His PCV system wasn't working then.

Wishmaster's87IROC

iTrader: (4)

you saying it wasnt work corrctly...well either way seems to work then? right? PVC or no PVC

Apeiron

Either one runs, but no PCV has increased oil contamination that leads to shortened oil life and accelerated wear.