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PCV wtih an IC (Spade and Sin..get in here)

BillBoost37

BillBoost37

New member
Ok, there was a very good discussion happening in chat and I'd like to see it discussed in a thread to get more insight and understanding. It's a common issue/concern.

Ok guys.. post it up.
 


Well, Pure is questioning running 2 front valve covers, which I disagree with, because the motor rocks towards the rear and a filler neck or oil cap backthere could leak, causing oil on the rear headers, which could result in engine fire and total loss of the vehicle.
 
I was talking about doing this to my car:

ClubGP Message Forum troubleshooting

I was/am going to do it slightly different though. I was going to run a front valve cover on the rear, tap the rear oil cap, install a PCV grommet and put the PCV valve into that. I would then run the line from the PCV valve to a catch can then to the EVAP port that I will have to tap on the back of the Gen V.
 
Yes.. so a little background..

Typically a different pcv solution is looked for when an IC blocks the factory pcv holes. ZZP puts a groove into the LIM to allow it to function. However many think that groove isn't deep enough to do the job. Expecially when you are spinning faster, quicker etc. The crankcase pressure can jump quickly and that groove is viewed as not being large enough to handle the volume of pressure that is built up. Some guys tap valvecovers etc.
 
Now that I'm thinking more about that, it should work. I personally would RTV the heck out of the valve cover you put in the rear to prevent leaks and treat it as if it were a rear (as far as never planning on using the cap).

I do see a problem tapping the cap due to clearance of the PCV valve like PRJ said in that thread, location is key. I would use the filler neck for the added clearance necessary to make that work.
 
If you are pulling the valve cover though.. why not tap into it and leave the added height of the cap/neck out of the equation. Seems like it would look cleaner w/o the cap/neck.
 


If you look at an oil cap...The neck is pretty long:
2

I would think it would clear also because the grommet actually makes the PCV valve sit up higher because of the rubber.

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Why do you need to add oil to the rear head? The oil that was sitting on the head when the motor was turned off is still there, except for the oil that drained to the pan, like every other time you turn it off.
 
Explicit_Spade said:
Have any of your locals done write-ups? I'd be interested.
Click to expand...

I posted up a little while ago. I will report back when I see what they say...

Most of them don't get up at the same time as you, Bill and I. lol

BillBoost37 said:
Why do you need to add oil to the rear head? The oil that was sitting on the head when the motor was turned off is still there, except for the oil that drained to the pan, like every other time you turn it off.
Click to expand...

I will delete that so people don't get confused. I was just kidding around. lol
 


Brian it wouldn't matter if it was plastic, aluminum, steel or wood, you can tap anything. And the valve covers aren't thick material anyway. What are they, like 1/16" thick? You're not going to have many threads to catch on at all. I say a grommet would work best in this situation.
 


I have tapped NPT 90 degree elbows into the sides of the front and rear valve covers, and ran them to an external PCV pulling vac from the top of the blower. Fresh air was drawn from a breather hose on the other side of the front valve cover going to the port on a northstar TB... To get it to function with a stock TB... you would have to build the stupid groove. or run an external maf on a stock TB with a fresh air draw between the blade and the external maf.
 
ZZP, WBS , and my intercooler have provisions for the Rear port to work through the intercooler. The rear port is where the crankcase air is coming up out of the engine, through the intercooler, through the supercharger and through the PCV and into the intake side of the supercharger. 1 hole must be drilled in LIM for this to work.! This one hole would mean that you don't have to modify the rear Valve cover.
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The front hole is the problem! This is where you want metered air (measured air) to fill the crankcase. This air should come from between the Throttle Body blade and the MAF and connect to the crankcase somewhere. I drilled the extension tube for the oil cap on my setup. Air in the front and pulled out the back.


 
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