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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Effects of air breathers with SD

  • Thread starter Thread starter 1991vert
  • Start date Start date Oct 31, 2007

1991vert

10 Year Member
Feb 27, 2004
1,103
7
69
Ludlow, MA
Oct 31, 2007
#1
  • Oct 31, 2007
  • #1
I will be running a FAST - XFI system in my car, which does not use a MAF. Now i know SD cars go nuts with any vacuum leak and i will be plugging the pcv valve opening in the lower intake. Would running breathers in each valve cover result in a vacuum or would I be fine because it's in the crank case?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Oct 31, 2007
#2
  • Oct 31, 2007
  • #2
You're good as long as the PCV is removed...

You don't want to be pulling fresh air into the crankcase, then into the intake.
That would be a vac leak.
You could tune around the leak with the FAST system, I'm sure...
But why would you?


You can't get vac in the crankcase without a source from the intake manifold, or maybe a pump if you're getting wild...

jason
 
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