I may be dumb, but--correctly venting an lsx w/o pcv?

[formula]

Alright so I've been researching how to correctly vent my engine after I swap to aftermarket valve covers. The engine is an l86 with ls6-style pcv hookups in the valley cover, but it was tuned with that hookup blocked off BUT the fresh air vent from the passenger side cover to the intake IS connected.

I've got a picture, hopefully this helps explain how things are configured. Sorry it's huge, but I feel like it'll make seeing what's up easier.

https://static1.pt-content.com/images/pt/2010/08/20319460-1.jpg

I'm switching to some Wegner valve covers and am trying to determine if it's best for me to just run a breather or a catch can or...what? And how should I plumb things? here's what came on the valve cover...

https://static1.pt-content.com/images/pt/2010/08/6b07d994-1.jpg

but this can obviously be removed and replaced if you guys can help me to plan a better alternative.

Since my car was obviously tuned without the PCV active, should I just leave that be? Should I just use the Wegner fitting provided and somehow run that to something like a norris catch can? Or even just a breather?

[Mike Norris]

With that hose running from the passenger valve cover to the intake port, which is direct vacuum, I would bet you are seeing some oil use and/or some oil smoke out of the tailpipe at times. Also I would bet there is a bunch of oil in the intake manifold.

Now, there is one thing that may be keeping the oil from getting through the intake, and that is whether or not there is a vent hose hooked up to get fresh air into the crankcase. If there is no other vent to fresh air, it will just build up a bunch of vacuum in the crankcase and no oil will move. But this will also destroy some of the oil seals over time and usually cause some odd noises while running.

One way to see if there is a bunch of vacuum on the crankcase is to let her sit at idle and try to remove the oil fill cap. If there is vacuum there it will be hard to pull off and when it does come off, there will be an inital loud sucking sound.

The way it is supposed to run is that a hose runs at the port from the valley cover under the intake, which in your pics has the red plug on it, to the port on the intake where your current hose is hooked up. That valley cover should have a proper built in PCV orifice to control airflow. The port on the passenger valve cover should have a hose run to fresh air in front of the throttle blade, but after the MAF sensor if one is being used.

Now, going to a proper PCV system will require it to be re-tuned, but should be worth it in the end.

With those covers you should be able to get or make a baffled oil fill cap vent. In the picture it is hard to tell, but it appears that the oil cap has some baffling at the bottom and if there is enough room between the cap and the baffling, perhaps a fitting can be fit there.

I would not do this, but of course if you want simple, you can just run a breather filter of the valve cover and just plug everything else at the intake and the valve covers and let it eat. Downside is that you will get some oil vapor smell and possibly oil residue or dripping at the breather.

Hope this helps.

Mike Norris

[formula]

First off, thanks a TON for your response, Mike! You may not have realized, but you actually tuned this engine for Frank, so I feel like you're the perfect person to talk to about this.


With that hose running from the passenger valve cover to the intake port, which is direct vacuum, I would bet you are seeing some oil use and/or some oil smoke out of the tailpipe at times. Also I would bet there is a bunch of oil in the intake manifold.

I was afraid you were gonna say that.



Now, there is one thing that may be keeping the oil from getting through the intake, and that is whether or not there is a vent hose hooked up to get fresh air into the crankcase. If there is no other vent to fresh air, it will just build up a bunch of vacuum in the crankcase and no oil will move. But this will also destroy some of the oil seals over time and usually cause some odd noises while running.


So it's not SUPPOSED to sound like a jet engine shutting down? damn.



One way to see if there is a bunch of vacuum on the crankcase is to let her sit at idle and try to remove the oil fill cap. If there is vacuum there it will be hard to pull off and when it does come off, there will be an inital loud sucking sound.


On the nosey, sir.



The way it is supposed to run is that a hose runs at the port from the valley cover under the intake, which in your pics has the red plug on it, to the port on the intake where your current hose is hooked up. That valley cover should have a proper built in PCV orifice to control airflow. The port on the passenger valve cover should have a hose run to fresh air in front of the throttle blade, but after the MAF sensor if one is being used.


When you say that the valley cover should have the built in orifice, do you mean that it SHOULD most likely already there or that it SHOULD be added? Just making sure I'm on the same page.




Now, going to a proper PCV system will require it to be re-tuned, but should be worth it in the end.


How serious of a retune is this? Is it the sort of thing where I could send you the PCM and it could be dialed back in, or is it more of a start-from-scratch deal? I hope the former as the car runs magnificently as it is now.



With those covers you should be able to get or make a baffled oil fill cap vent. In the picture it is hard to tell, but it appears that the oil cap has some baffling at the bottom and if there is enough room between the cap and the baffling, perhaps a fitting can be fit there.


It is baffled and threaded--I'll have to get a better picture of it to show what's up there.



I would not do this, but of course if you want simple, you can just run a breather filter of the valve cover and just plug everything else at the intake and the valve covers and let it eat. Downside is that you will get some oil vapor smell and possibly oil residue or dripping at the breather.

Hope this helps.

Mike Norris

I like the idea of doing it the right way!

Short term, until I can get a retune taken care of, is it wiser to leave things as they are, or go ahead and reroute to the pcv and figure out a way to get filtered fresh air in to the valve cover?

Thanks again, Mike!

[Mike Norris]

Hi Wes,

I do remember the car and wish I looked it over a bit more closely.

The valley cover should be all set to go as far as having a built in orifice for the PCV, so no extra work there.

The tuning may be simple, but without proper data I would be guessing at best.

In the meantime you could set it up as I mentioned last and just plug the port at the intake and put some kind of small filter on the hose off the valve cover to at least let it breath. That should keep the tune close to what I had and maybe just a tick richer, which would be to the safer side.

Hope this helps again.

Mike Norris

[NovaJ]

... The port on the passenger valve cover should have a hose run to fresh air in front of the throttle blade, but after the MAF sensor if one is being used...


I wanted to ask about this part because I just got done hooking this part up, but on my LY6 intake there is a port behind the throttle and probably within 2 inches of the throttle. I hooked the hose from the fresh air intake on the passenger valve cover to this port on the intake. So my question is, will I be okay with this arrangement? Or do I need to try and change it?

Thanks

[Payton King]

on LS1Tech. I did a google search and found it. I think I looked at LS1 oil catch can. It was about a 10 page thread with the correct configurations with one or two catch cans, turbo and blower set-ups. Very good stuff. I am going to order a couple of catch cans from www.saikoumichi.com (http://www.saikoumichi.com) .

I am about to change my configuraton. I am running the LS6 valley pan and have that going to a catch can and then through a PVC valve and to the lower port on my Fast intake. I plugged the valve cover vents and it caused pressure which push oil past the knock sensors making an oil leak.

I plan on getting another can and run the vent from the valve cover to the catch can and then to the upper port on my Nick Williams throttle body. The top port is metered air so I will not run lean. The port from the valve cover needs to breath both ways. At WOT there is not much vaccum but there will be a lot of pressure that needs to get out.

Does all of that make sense?

I will be at RTTH, look me up or I will hunt you down. Love to take a closer look at your car.

[Mike Norris]

NovaJ,

If you have a hose running from any valve cover port to any intake manifold port, most likely it is wrong and set up similar to what Formula has in his first picture I would imagine.

The exception to that rule is if a car has DOD or AFM that kills cylinder per power demand. On these engines, the hose for the PCV runs from the back of the drivers valve cover to a specific port on the intake.

Now if you have a TB like what Payton is describing with a port coming off of it right at the flange where it bolts up to the intake, that would be fine as that port does not have vacuum at it.

Hi Payton,

The way you are going to set it up is correct for sure, except you need to use my catch cans :hammer: Just kidding, those units work very well also.

Mike Norris

[Payton King]

Show me what you have.

The one i am running now is from CCA that I got off of the Corvette Forum.

Since I am going to run 2 they need to match. LOL

[Mike Norris]

The CCA can is my can and they are one of my good dealers. Here is the link to my site with the info.

http://www.mikenorrismotorsports.com/Billet_PCV_Catch_Cans.html

I do have a double can bracket also available to run two cans side by side.

I have another run of 150 or so to be ready in about 2-3 weeks.

Hope this helps Payton and thanks.

Mike Norris

[formula]

You guys are great, I love this forum--such a massive knowledge base.

Mike, I will reconfigure as you said as a patch fix to get me through rtth. I may have a tough time getting up to your new place for a retune, though. Do you think you could recommend a colleague near the carolinas that could help me with a retune once I have everything reconfigured properly? Feel free to PM me if you'd prefer. Also, is there any chance we can get a peek at what your double-can setup looks like? I was planning on running your cans anyway, but I like the idea of filtering both lines.

Payton, I look forward to checking out your setup as well! I've been looking forward to seeing your car ever since JC/Cheapthrillz bought your balance bar last year--I was the other guy with him, haha.

[Payton King]

My motor is sitting on a stand right now. Lost pressure at Zmax on a test and tune night. Hopefully I will have it back in this weekend and get my new clutch broke in before I get there.


Mike, I would like to see that double bracket...got any pics

[Mike Norris]

I found a couple, one in raw before anodizing and the other mounted and anodized black.

The can with the breather is one customized by a customer, so before you ask.........:cheers:

Mike Norris

[NovaJ]

NovaJ,

If you have a hose running from any valve cover port to any intake manifold port, most likely it is wrong and set up similar to what Formula has in his first picture I would imagine.

The exception to that rule is if a car has DOD or AFM that kills cylinder per power demand. On these engines, the hose for the PCV runs from the back of the drivers valve cover to a specific port on the intake.

Now if you have a TB like what Payton is describing with a port coming off of it right at the flange where it bolts up to the intake, that would be fine as that port does not have vacuum at it.

Thanks for answering my question Mike. My motor has VVT but no DOD, and has a fresh air intake on the front of the passenger valve cover, and the outlet is on the back of the driver valve cover and goes to a port that is in the middle and on the top of the truck intake (has a red cap in the example picture). I placed the fresh air intake on the port where the EVAP purge solenoid outlet enters the intake in the picture. Will this forward spot have too much vacuum and pull air out of the passenger valve cover instead of the way it is all supposed to work? It is hard to tell in the picture, but the forward port is still in the "main tube" of the intake, and not really in the same area as the runners to the cylinders.

Example picture pulled from the web (not my intake)...

http://img.villagephotos.com/p/2004-6/746244/LS2_TBSS_intake01.JPG

Also, I apologize if this is straying from the original thread starter's topic too much.

Thanks again.

[formula]

Not at all, my engine is ex-dod (cam swapped) so I'm wondering if this may be pertinent to me as well.

[formula]

Mike,

I've reconfigured the lines per the temporary fix you suggested and the engine seems much happier--maybe that's just a placebo effect, though. Regardless, it's at least breathing normally now, and all my whooshing and whistling is gone. Thanks again for your help!