Jump to content


Photo

Pcv And Cam Cover Breather Options


  • Please log in to reply
201 replies to this topic

#1 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 09:13 AM

As title after discussing it with joe in his forsake hoarder thread

#2 haggi961

haggi961

    1cobrav8 is my god

  • PipPipPipPipPipPipPip
  • 6,003 posts
  • Gender:Male
  • Location:Richmond, N.Yorks
  • Interests:Keeping fit and in shape, and pretty much anything to do with an engine.

Posted 12 April 2014 - 09:18 AM

I'm also wanting to know what i should do as I'm still undecided. With the Dutch software you can run this open but the CS software you need it blocked up as they can't map the car with it open. I had a email off Peter about it = About the PCV system, for the software it does not matter whether you are using the PCV system or if you choose to block it. When unblocking it, just do a part throttle fuel learning and everything will be OK. For the engine it is better to have the system working because it will give better crank case ventilation when cruising. With the Z22SE cylinder head, the PCV does not line up nicely to the PCV in the inlet manifold so you have to make a sort of channel to line them up correctly. I have never heard of problems with oil getting into the engine with the PCV system enabled but you should attach an air filter to the cam cover breather with a working PCV system. With the PCV working the air is reversed and sucked into the valve cover when cruising and there for this air must be filtered. The OEM cam cover ventilation is on the small side for big powered engines. In some cases you can make the hole slightly bigger by drilling away the aluminum inside the valve cover behind the pipe. Some people also make an extra hole into the oil filler cap or some other location to give the engine more room the breathe.

#3 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 09:20 AM

At the moment I am gunning with the PCV open to the manifold but at croft the other Friday my dipstick came out of engine slightly The cam cover was also passing some oily stuff which is currently vented to atmosphere

#4 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 09:22 AM

From what peter has said to Haggie my Pcv must not be working

#5 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 09:23 AM

Has anyone got a way of testing the PCV

#6 haggi961

haggi961

    1cobrav8 is my god

  • PipPipPipPipPipPipPip
  • 6,003 posts
  • Gender:Male
  • Location:Richmond, N.Yorks
  • Interests:Keeping fit and in shape, and pretty much anything to do with an engine.

Posted 12 April 2014 - 09:27 AM

I've never had a problem with my dipstick coming out and mines been blocked for years, I've also never got any oil build up out of my cam cover breather so I'm still sort of going the blocked route.

#7 The Batman

The Batman

    Super Moderator

  • 30,267 posts
  • Gender:Male
  • Location:FLD mum's bed

Posted 12 April 2014 - 09:29 AM

I agree I think the dipstick coming out was a coincidence/fitting mistake.

#8 fezzasus

fezzasus

    Whipping Boy

  • PipPipPipPipPipPipPip
  • 7,689 posts
  • Gender:Male
  • Location:Oxford

Posted 12 April 2014 - 09:31 AM

For reference

 

original design

 

Excess gas and oil vapour is vented from the port between the inlet ports on the cylinder head. The vapour is mixed with the fresh air in the inlet manifold and burnt off during normal combustion.

 

Fresh air is pulled in from the cam cover which connects to to the intake pipe after the air filter to ensure the fresh air is filtered.

 

During full throttle applications, the PCV vent closes (there is too much pressure in the manifold and it will actually pressurise the crankcase). This effectively reverses the flow and some gas/vapour will come out of the cam cover

 

CS modification

 

The exhaust vent into the inlet manifold is blocked. This results in just one vent to atmosphere (cam cover) as there is now air trying to flow both out and in through the same hole 'bumping' happens, where volumes of oil are ejected. It's exactly the same as holding a full bottle upside down and letting the liquid drain out - it gluts/bumps as it lets liquid out and air in. This results in higher oil loss.

 

OBD tuner implementation

 

This is exactly the same as the original implementation of the PCV, however the cars typically have higher rev limits which means more time with the PCV vent closed. The implication of this is more time using the cam cover for both venting and pulling in fresh air. Not a problem when an NA, but if this is directly connected to the inlet manifold when supercharged there will be oil pulled into the laminiovas. Place a catch tank or oil filter in line, or use a small separate air filter.

 

So Chris, the reason your car behaves like the PCV is blocked is because you've got a high rev limit, and at high revs the PCV is blocked.


Edited by fezzasus, 12 April 2014 - 09:33 AM.


#9 haggi961

haggi961

    1cobrav8 is my god

  • PipPipPipPipPipPipPip
  • 6,003 posts
  • Gender:Male
  • Location:Richmond, N.Yorks
  • Interests:Keeping fit and in shape, and pretty much anything to do with an engine.

Posted 12 April 2014 - 09:32 AM

Was does your dipstick feel like to push in and pull out as I know mine is not easy and takes some pulling.

Edited by haggi961, 12 April 2014 - 09:32 AM.


#10 techieboy

techieboy

    Supercharger of Doom

  • 22,914 posts
  • Gender:Male
  • Location:Bedford

Posted 12 April 2014 - 09:36 AM

I've never had a problem with my dipstick coming out and mines been blocked for years, I've also never got any oil build up out of my cam cover breather so I'm still sort of going the blocked route.

Same as that.  

I agree I think the dipstick coming out was a coincidence/fitting mistake.

But the Yanquis do complain that they have dipstick ejection issues on the LSJ's and increase the size of all of the external breather systems on the higher powered cars. If the Z22SE and B207 cam covers weren't such a pain with the riveted baffle plate, it would make more sense to increase the size of the breather vent to -10 fittings like some of them have. Would also make sense to put the fitting on the "high" side of the B207 cam cover, like the Z22SE

Edited by techieboy, 12 April 2014 - 09:38 AM.


#11 The Batman

The Batman

    Super Moderator

  • 30,267 posts
  • Gender:Male
  • Location:FLD mum's bed

Posted 12 April 2014 - 09:37 AM

That's mainly on the turbo conversions though isn't it?

#12 techieboy

techieboy

    Supercharger of Doom

  • 22,914 posts
  • Gender:Male
  • Location:Bedford

Posted 12 April 2014 - 09:38 AM

Nah, SC as well.

#13 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 09:39 AM

@ tom thanks for that, it explains why it's only happening on track @ Luke it a tight fit Tom am I right in thinking that when Pcv is closed under high rev does the cam cover then blow again instead of sucking, If so what can be done to stop this, Also is it a option to vent the crank direct from the bottom of block the way it was done before Pcv was invented

#14 fezzasus

fezzasus

    Whipping Boy

  • PipPipPipPipPipPipPip
  • 7,689 posts
  • Gender:Male
  • Location:Oxford

Posted 12 April 2014 - 10:00 AM

Is there anything in the LSJ build book about it? 

 

You could just put another vent in, however working out where might be an issue. I've seen someone who drilled an oil filler cap to put a wider bore vent in there. Might be the best option to test if it works.



#15 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 10:02 AM

I was thinking more like a vent lower down similar to the gearbox breather mod so if any oil was swept up it could drain back down

#16 techieboy

techieboy

    Supercharger of Doom

  • 22,914 posts
  • Gender:Male
  • Location:Bedford

Posted 12 April 2014 - 10:06 AM

I've seen someone who drilled an oil filler cap to put a wider bore vent in there. Might be the best option to test if it works.

I've got a vented filler cap from the States in the garage. I had a look when I first got it and don't think it will fit with the standard engine cover, once the AN hose and fittings are connected up as it's so tall - obviously not a problem on the Cobalt and the multitude of Chevy cars that the cap appears to fit. Sticky modified his OEM filler cap and attached an extra breather hose to it.

#17 haggi961

haggi961

    1cobrav8 is my god

  • PipPipPipPipPipPipPip
  • 6,003 posts
  • Gender:Male
  • Location:Richmond, N.Yorks
  • Interests:Keeping fit and in shape, and pretty much anything to do with an engine.

Posted 12 April 2014 - 10:13 AM

This looks the best option if your going to vent the filler cap.

Posted Image

#18 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 10:30 AM

I'm not doing that, it looks dreadful and that's from someone that normally doesn't care about looks.. I would like to vent the crank case direct Not relying on cam cover and head Could this be done or am I barking up the wrong tree??

#19 fezzasus

fezzasus

    Whipping Boy

  • PipPipPipPipPipPipPip
  • 7,689 posts
  • Gender:Male
  • Location:Oxford

Posted 12 April 2014 - 10:36 AM

I was thinking more like a vent lower down similar to the gearbox breather mod so if any oil was swept up it could drain back down

 

I would try the vented oil filler cap before doing anything more drastic. It's effectively non-destructive as you just replace the cap. 

 

Only other place I can think is the Turbo drain channel which was blocked up, however that's almost too low down. I would imagine a lot of oil will be pushed out from the sump.



#20 CHILL Gone DUTCH

CHILL Gone DUTCH

    I ADMIT BATMAN THINKS HE IS QUICKER THAN ME

  • PipPipPipPipPipPipPipPip
  • 13,727 posts
  • Gender:Male
  • Location:UK

Posted 12 April 2014 - 10:39 AM

Would you just put a filter on it or join it like the pic




3 user(s) are reading this topic

0 members, 3 guests, 0 anonymous users