a PCV layout for a boosted engine
#101
None of these suggestions would work if your running an MAF Blow through tune...
actually, none of these appear to work properly with any MAF vehicle as any air pulled around is un-metered, is everyone SD?... is there a different setup to accommodate for this? or am i missing something here...
I would think a crankcase vacuum scavenge external pump system was the only way ESPECIALLY when you start putting 'cute' k&N's somewhere to the atmosphere.
Sorry if I dug this out of the grave...
actually, none of these appear to work properly with any MAF vehicle as any air pulled around is un-metered, is everyone SD?... is there a different setup to accommodate for this? or am i missing something here...
I would think a crankcase vacuum scavenge external pump system was the only way ESPECIALLY when you start putting 'cute' k&N's somewhere to the atmosphere.
Sorry if I dug this out of the grave...
Last edited by vmapper; 06-04-2010 at 04:00 PM.
#102
None of these suggestions would work if your running an MAF Blow through tune...
actually, none of these appear to work properly with any MAF vehicle as any air pulled around is un-metered, is everyone SD?... is there a different setup to accommodate for this? or am i missing something here...
I would think a crankcase vacuum scavenge external pump system was the only way ESPECIALLY when you start putting 'cute' k&N's somewhere to the atmosphere.
Sorry if I dug this out of the grave...
actually, none of these appear to work properly with any MAF vehicle as any air pulled around is un-metered, is everyone SD?... is there a different setup to accommodate for this? or am i missing something here...
I would think a crankcase vacuum scavenge external pump system was the only way ESPECIALLY when you start putting 'cute' k&N's somewhere to the atmosphere.
Sorry if I dug this out of the grave...
#103
Negligible? Really? Last time I changed to and open PCV the idle went haywire, did a scan.. and the computer pulled timing big time to bring it back... thats becuase its UN METERED air. Maybe a pinhole, but your talking a considerable CFM count. Every tweaked table would be out in regards to cylinder volume and the Proper tune is out to lunch.
As mentioned... NOT running SD, but MAF only... I would not compromise, espeically on a blown car, to 'LET the computer handle the 'un' metered air leak.
So your HOPING, ONLY if your in Closed loop, that the Narrow band O2s see this extra air and enrich?
I think if it was beaten to death and the conclusion was 'negligible' and the computer was to adjust is a naive conclusion and clearly dont know the details of the ECM.
#105
Well, when I look at that diagram I think,
It would work if you are running SD (Speed Density Tune)...
Will not if your running with a tune that uses a MAF.
And again.. I want to know why 05TurboCGM likes to create vacuum leaks for his ECM to adjust for, causing the inability to get the BEST out of a tune... I wish Greg Banish would post on this.
It would work if you are running SD (Speed Density Tune)...
Will not if your running with a tune that uses a MAF.
And again.. I want to know why 05TurboCGM likes to create vacuum leaks for his ECM to adjust for, causing the inability to get the BEST out of a tune... I wish Greg Banish would post on this.
#106
12 Second Club
iTrader: (13)
Joined: Nov 2001
Posts: 1,898
Likes: 0
Received 0 Likes
on
0 Posts
From: San Diego, CA
No need for Greg Banish to come save the day, LOL. My setup doesn't allow unmetered air (which is one of the reasons I don't use a breather in the PCV system). Post #49 in this thread. There are a million ways to do this, and a million different opinions on how to do it. This topic gets beat to death.
Just like every other post on this board, read and make an educated decision for yourself.
Rob (Bad30th)
Just like every other post on this board, read and make an educated decision for yourself.
Rob (Bad30th)
#107
so what would you change for a maf setup? from my understanding at idle the setup would work as normal, fresh air in the blue line and vented to the throttle body by the red, then under boost the check valve would close off the one line but the turbo would pull the crank pressure through the blue line and recirculate it back in through the maf? where would the unmetered air come in?
#108
No need for Greg Banish to come save the day, LOL. My setup doesn't allow unmetered air (which is one of the reasons I don't use a breather in the PCV system). Post #49 in this thread. There are a million ways to do this, and a million different opinions on how to do it. This topic gets beat to death.
Just like every other post on this board, read and make an educated decision for yourself.
Rob (Bad30th)
Just like every other post on this board, read and make an educated decision for yourself.
Rob (Bad30th)
what Im saying is, where is the fresh air coming from? or are you actually creating a vacuum within the crankcase? (not a ventilation so to speak and then creating a vacuum in the crankcase via manifold during light throttle and idle.
Like a double sided vacuum? - I suppose that would work, not really circulation of air.. but always under vac?
Am I understanding that right?
You dont need to re-explain.. As I see you have done a decent job prior, and what I wrote above is what you are getting at. an Actual Vacuum vs circulation.
Last edited by vmapper; 06-07-2010 at 04:01 PM.
#109
so what would you change for a maf setup? from my understanding at idle the setup would work as normal, fresh air in the blue line and vented to the throttle body by the red, then under boost the check valve would close off the one line but the turbo would pull the crank pressure through the blue line and recirculate it back in through the maf? where would the unmetered air come in?
In pressurization, its dead.. check valve preventing circulation and you create a vacuum in the crankcase... I guess is fine.. but idle (high manifold vacuum) its pulling air pre-turbo.
Thats what i get out of that diagram... only works half time.
Last edited by vmapper; 06-07-2010 at 04:18 PM.
#113
Here is over 800 posts of hell:
http://www.iwsti.com/forums/2-5-lite...ns-thread.html
Last edited by vmapper; 06-08-2010 at 05:07 PM. Reason: added url link