WayneA

I did some searches and found a few discussions on both mostly on using one or the other but not which to use. My primary reason for using either is the addition of a KB supercharger this year.

I think we can mostly agree that oil in the intake via a PCV valve is not good for the engine. The PVC system was designed to vent the crankcase not crankcase, not lubricate the intake. I suppose the auto manufactures find it acceptable to introduce the oil vapor into the intake with no major impact to the engine. My question is...

Is the vacuum from the intake needed to help vent the crankcase? If not, why are people using an oil separator? Why not just use a breather or breather/catch can setup?

I’m assuming most twin screw superchargers would have a PCV connection on the non charged side of the intake. This would keep boost from getting to the engine from the PCV system but would still allow the oil to get on the supercharger and intercooler.

-Wayne

metroplex

Actually the PCV blowby is designed to lubricate the combustion chamber (somewhat) to help the rings seal better. This is how it has been done for a long time. The problem with the supercharger is that the oil also finds its way into the intercooler reducing the heat transferring capacity. For a naturally aspirated application, keep it as is.

Ford's other engines, like the 2.3L DOHC I4, has a factory equipped oil separator that redistributes the oil back into the engine block.

Darth Stang

So is there any harm in adding one to a supercharged 3V engined?

metroplex

No, there's no harm in adding one for a forced induction application. Most gasoline additives already contain lubricants for the cylinder walls.

I'd be careful about the type of separator being used. Most polycarbonate bowls are not rated for cold or extremely hot weather use and can crack. A leak in the PCV can cause the engine to stall out.

DoctorQ

I asked this very question a few months back (Is there any benefit to PCV blowby on a NA S197)... all responses were no (given it was collecting in intake and not being completely burned off). Quite a few Forum members (including myself) have installed oil separators on our NA GTs. Are you saying there could be detrimental effects on NA motors by running oil separators (and filtering oil out before it can get back into the intake)? I've been running with a Moroso tank for a few months.. what type of symptoms would I be seeing if rings are not being lubricated? Thx.

300HPGT

All I can say is that I can get away with running a lower octane fuel with more spark using a separator. im running my 93 octane tune on 89 in California thanks to my separator.

WayneA

For everyone that thinks that oil should be introduced into the intake for lubrication purposes here’s a picture of CMCV plates. I think the use of an oil separator or breather is needed on a NA or PI engine. The question is which to use. Can I get away with a breather, no vacuum or do I need a oil separator that has a vacuum effect on the PCV valve?


-Wayne

The Reverend

Those pictures might sell me on the Steeda economy delete plates.