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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Breather With Pcv?

  • Thread starter Thread starter jrp27540
  • Start date Start date Mar 21, 2017
J

jrp27540

Active Member
Sep 9, 2016
173
35
38
Mar 21, 2017
#1
  • Mar 21, 2017
  • #1
I was reading through an article(link below) from BAMA Performance around idle performance technical tips, as I am currently running a BAMA chip.

The following information threw me for a loop: "If you are running a breather you cannot keep the PCV installed on the other side - please remove the PCV completely. Most street engines can benefit from a proper PCV system with Fresh Air Intake to provide a clean source of Fresh Air into the crankcase system (this is the hose going from the inlet tube to the air intake pipe)"

So I have been reading threads to educate myself on this topic about breathers vrs. PCV. Ends up there is a lot of debate on the subject. Currently, I have a breather on the passenger side VC(link below), and a PCV on the driver side VC. After reading posts, It appears that my setup is wrong as I'm allowing unmetered air into the system. If I remove the PCV valve, then I no longer have unmetered air going back into the intake via the PCV valve from the breather.

My concern with following BAMA's recommendation is possibly having to much crank case pressure with my e303 cam using only one breather. Would it be best if I run a breather on each side rather than just plugging up the PCV hole?

Feedback would be appreciated. Thanks!!!

Current breather:
https://lmr.com/item/SB-261522/Mustang-Screw-In-Valve-Cover-Breather-86-00

BAMA's article:
https://support.bamaperformance.com...04-Mustang-Idle-Tuning-Basics-Mechanical-Tips
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Mar 22, 2017
#2
  • Mar 22, 2017
  • #2
You either run breathers or a pcv, not both. I used to run a vented breather tank due to my victor efi intake not having pcv. Ended up converting the car back to pcv to avoid the fumes.
 

wgreenlee4

Member
Jun 12, 2011
27
5
14
Mar 26, 2017
#3
  • Mar 26, 2017
  • #3
If it is easy to set up I don't see why you couldn't run a breather on both sides. You can never have too much crankcase ventilation as long as it's filtered. Or you can properly connect the PCV system so it is metered.
 
J

jrp27540

Active Member
Sep 9, 2016
173
35
38
Mar 29, 2017
#4
  • Mar 29, 2017
  • #4
Thanks for the feedback everyone. I decided to move back to PCV. I read through a different the thread where someone mentioned breathers emitting fume vapors and the vapors being blown back into the interior. I currently struggle with this and wrote it off as a possible exhaust leak on one of the headers. I'm going to try and see if this makes a difference on the fume vapors.
 
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