Effects of air breathers with SD

[1991vert]

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]

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