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Discussion Starter · #1 ·
I have a 96 lt1 engine that is out of a camaro that I put in a 56 chevy. I just want to make sure I have the pcv hooked correctly. So here it goes, I have the pcv that is located on the side of the intake manifold, hooked to the vacuum source on the front of the air door per the website "shbox". Now this is the part I am unsure of the system should have a breather but on the passenger side valve cover. The motor i have has a pcv valve in it with a valve, so I gutted the valve out to act just as a breather and ran the hose to the top of the air door. Is this correct? Let me know if this sounds right to you guys.
 

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Air door? Do you mean the throttle body?

http://shbox.com/1/pcv_pipe.jpg

The fresh air inlet hose to the RH valve cover goes to the top port on the side of the TB shown here.

There is only a plastic elbow on the end of the hose at the valve cover. This is a closed system, so there is no "breather".
 

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Discussion Starter · #3 ·
Air door? Do you mean the throttle body?

http://shbox.com/1/pcv_pipe.jpg

The fresh air inlet hose to the RH valve cover goes to the top port on the side of the TB shown here.

There is only a plastic elbow on the end of the hose at the valve cover. This is a closed system, so there is no "breather".
yes, sorry I got in the habit of calling it an air door. I definitely have the PCV hooked up correctly. So when you say there's only a plastic elbow there is no other valve just an open end to the baffle of the valve cover correct? This would in fact act as a "breather" than as it is venting directly into an open passage on the throttle body. Right?
 

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Not a breather in the traditional old school sense (like an open air vent stuck in the top of a valve cover). The air supplied from the TB is metered by the MAF and accounted for by the computer. Air flows from the TB into the crankcase under normal conditions and is sucked back out through the PCV valve and then ingested via the intake manifold. During periods of very high throttle, when there is low vacuum, air can also go from the valve cover back toward the TB.
 

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Is it ok or better or both to just do away with that hose between the TB and valve cover and just cap the TB nipple and run a push in breather filter?

What about adding a "catch" device in the PCV line?

Not a breather in the traditional old school sense (like an open air vent stuck in the top of a valve cover). The air supplied from the TB is metered by the MAF and accounted for by the computer. Air flows from the TB into the crankcase under normal conditions and is sucked back out through the PCV valve and then ingested via the intake manifold. During periods of very high throttle, when there is low vacuum, air can also go from the valve cover back toward the TB.
 

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a breather filter on the passenger valve cover sure wont hurt anything if you want to delete the hose. at high rpm when the intake side of the pcv system doesnt work worth a crap, that hose running to the throttle body wont produce much vacuum anyway, certainly not enough to pull the pressure in the crankcase into a state of vacuum to remove any substantial amount of vapors

for a loosely built or boosted race engine (or a really old motor with a ton of blowby) a catch can isnt a bad idea, as they tend to just spew oil through the PCV. your engine already has a type of catch can built in (windage trays and such), and a little bit of oil being burned from the crankcase will cause no harm
 

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to avoid confusion, shbox, we aren't talking about deleting the entire pcv system.. we're talking about running a breather on the fresh air inlet side (on the passenger valve cover), which will function exactly the same as the stock pcv system except near WOT.
 

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So when the PCV valve is open the MAF senses more airflow? How does that happen since the MAF is before the intake manifold?

It won't function exactly like the stock system (since the air being pulled in by the breather is not measured by the MAF), but will be close.
 

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my experiments show a 1-2 difference in trims (towards rich) when that port in the throttle body is plugged and the valve cover runs a breather instead, which is definitely not a big deal
 

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Is this the port that causes oil to go into the TB and intake?
 

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at anything but extreme throttle, stuff comes in the pcv (drivers side hose)

at more extreme throttle, stuff can come in the fresh air inlet as well due to excess crankcase pressure (passenger side)
 

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Sorry to bring up an old thread... But I'm finally fixing my hoses and lines that weren't on the motor after the rebuild.. I've pretty much got an idea as to where the hoses yall were talking about go..
but my question is, now on the driver side. I've got a hole in my valve cover towards the back (similar to the passenger side) .. What goes here?? and where does it connect to afterwards?
 

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Sorry to bring up an old thread... But I'm finally fixing my hoses and lines that weren't on the motor after the rebuild.. I've pretty much got an idea as to where the hoses yall were talking about go..
but my question is, now on the driver side. I've got a hole in my valve cover towards the back (similar to the passenger side) .. What goes here?? and where does it connect to afterwards?
There should be no holes in the driver's side valve cover as stock. There is nothing to put in there.
 

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Shoebox, ur just the person I was hoping would comment. I checked out your website and looked all over online and couldn't figure out what goes there?? But thanks for clearing this up with me.
I just got my car running after a few years, and after having my headers welded on I drove it and noticed it idling wayy to high.. I changed the i.a.c. valve and have fixed all or most of the vacumm leaks it had because most of the hoses were missing and I was stumped on this last part so today after I install my new battery I'm hoping to have this fixed.
 

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also it seems that they have done the throttle body by-pass on my car.. now my question is, the steam line thats hooked up to the back of my heads is hooked up correctly, now as far as the metal line that runs up towards the front of my motor (after it connects to both heads in the rear) what do I do with that line? at the moment its capped off, but im not sure if thats correct or not and if it isn't i'd like to correct it while im dealing with the rest of these lines.
 

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someone must have put the wrong valve cover on there; a factory LT1 has no holes or fittings whatsoever in the drivers side valve cover.

can you post some pics of the hoses on both sides so we can figure out if you have it right?
 

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also it seems that they have done the throttle body by-pass on my car.. now my question is, the steam line thats hooked up to the back of my heads is hooked up correctly, now as far as the metal line that runs up towards the front of my motor (after it connects to both heads in the rear) what do I do with that line? at the moment its capped off, but im not sure if thats correct or not and if it isn't i'd like to correct it while im dealing with the rest of these lines.
The steam pipe hose goes to the radiator. You don't want it capped off.
http://shbox.com/1/tb_bypass.jpg
 
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