Raphs50

I am re-posting this question because I can't believe ALL CAPS guy is getting more responses on his question. Maybe I was a little wordy on my first post. If you want to read the background, it is here:
https://mustangforums.com/forum/5-0l...tered-air.html

My question is, with a supercharger, you can't have the air line from the valve cover to upper intake connected, right? It creates too much crankcase pressure from the s/c. So shouldn't the PCV be diconnected too, or won't unmetered air (not coming through the mass air meter) get pulled in through the beather on the valve cover and in to the intake via the PCV? Isn't is a bad idea to "tune around" this problem because of changes in temperature, pressure, etc.? Tried disconnecting my PCV (plugging the holes in the intake obviously) and it ran like crap.

Anyone understand all this ECM stuff?

mjr46

Care to explain who you mean by all caps guy?? hope you don't mean PRO50SC

Raphs50

Of course it was not Pro50SC. It was referring to a post from a new member in the General 5.0 discusison forum.
https://mustangforums.com/forum/5-0l...ttle-help.html

Probably should have just stuck to my question, especially since I am asking for help. My bad.

mjr46

pm PRO50SC he has a write up that'll show you how to route the system properly

Raphs50

OK, I will do that, thanks.

stanks347

I have my hose running from the valve cover through a filter and dumping into the air box assembly.

Raphs50

That is how I have it also (well I have no air box, so it is in the fender well next to the air filter), but if you feel the end of that hose, it is sucking in air. There is some blow-by in crankcase, which should create some positive pressure on that hose. Since it is sucking air, the intake must be pulling air through crankcase and PCV into the intake. Since it is unmetered air, the computer can't accurately account for it.

NoGo95GT

Not sure if this will work for you but, I run a breather on my passenger valve cover and run my pvc line with two catch cans to my driver side valve cover. it seems to work good.

chickenbutt

I have a supercharger on my 5.0 and had my hose conected from the valve cover to the throttle body.. So i should take this off?? can I plug the t body side and use a filter on the valve cover? and what about this pcv valve? im not sure where its located. and what should I do, im not really understanding what you are talking about here. thanks.

Raphs50

Yes, you want to plug the throttle body side and use a breather on the valve cover (or just run a hose to near the air filter). The PCV valve is located on the back of your lower intake. It's kind of hard to see with the upper intake on. It pushes into a rubber grommet on the lower intake. It has a hose connected to it that runs to the upper intake so that gases venting from your crankcase are sucked in to the intake and burned up in combustion. If you put a breather or hose on the valve cover, it's no longer a closed system, so the intake can suck air through the breather, through the crank, through the PCV valve and into the intake. Since this air doesn't go through the mass air meter, the computer can't account for it, and the engine will run lean.