Do I need this?

[bigtyme1]

Hey guys, I'm finally getting around to cleaning up the engine compartment a little. Got some smooth covers from Street and performance and the driver rear is choking me up a little. There's a vac line coming off the back of the LS6 manifold going to the valve cover in the rear. Can I block it off? The problem is the hose sticks up to high and it hits the covers. Is there a plug with a 90 degree port? or just block it off ?

http://i941.photobucket.com/albums/ad251/bigtyme1/motorcovers.jpg

http://i941.photobucket.com/albums/ad251/bigtyme1/vacuum.jpg

[brans72]

not 100% sure but looks like some type of breather or pvc valve just what comes to first thought. Another is for vaccum like the brke booster after looking closer on which head it was on.

[Mike Norris]

I would be curious to what port on the intake that the hose is running to that valve cover. It should not be going to the intake manifold. If you are running a hose from the 1/2" hose on the back of the intake to the drivers valve cover rear port, this can be a big issue if it does not have some kind of PCV valve in that line.

Here is how the hoses should be run on a stock LS1 engine, regardless of an LS1 or LS6 intake.

The rear of the drivers valve cover crosses the back of the engine and "Y"s with the rear of rear port of the passenger valve cover into a single line and then to the PCV valve. Then from the valve it runs into the port at the front of the intake on the passenger side just behind the throttle body. This makes up the vacuum side of the PCV system.

The port on the front of the passenger valve cover goes to the port on the throttle body on the passenger side near the throttle stop. This is the fresh air or breather hose.

On the back of the intake, the large hose (1/2") is your vacuum line for a brake boost. Since you have manual brakes, this port should be blocked. There is also a small port (1/8"?) that is normally used for vacuum access for the AC or other accessories. This can also be plugged off if need be.

That is is as far as "normal" goes.

With not being able to see what you have going on with the passenger side valve cover ports, I am hard pressed to tell you what you need to do, but here are a couple ideas based on the above "normal" setup.

You can eliminate the drives port by plugging it off and just running a single hose from the passenger valve cover rear port to the PCV valve and then to the port at the front passenger side of the intake just behind the throttle body and then keep the breather hose as "normal".

You can again eliminate the drivers valve cover port by plugging it off and then running a new PCV hose from the rear of the passenger valve cover to the 1/2" vaccum port at the rear of the intake, but you WILL NEED to add a PCV valve to this line to make it work properly. If you do this then you can again run the breather hose as "normal".

Now if you do have it setup as I am thinking from the first paragraph with no PCV valve and had it custom tuned this way, it will have to be retuned if you go and set it up the "normal" and proper way. This is due to the rate of change in how much air will be traveling through the PCV system.

Hope this helps.

Mike Norris

[bigtyme1]

Mike, I'm using an LS6 Manifold does this make a differance.

[Mike Norris]

No sir, the ports are the same be it an LS1 or LS6 intake. I did forget one prot which is on the drivers front of the intake just behind the TB. It is used for the EVAP system on a stock LS setup and usually plugged off on a hybrid install.

Mike Norris

[bigtyme1]

No sir, the ports are the same be it an LS1 or LS6 intake. I did forget one prot which is on the drivers front of the intake just behind the TB. It is used for the EVAP system on a stock LS setup and usually plugged off on a hybrid install.

Mike Norris

Just tried to call you at the shop

[brans72]

Let us know what you find out please.

[Mike Norris]

Good talking to you today. let me know how it works out.

Mike Norris

[bigtyme1]

Good talking to you today. let me know how it works out.

Mike Norris

Thanks Mike, I went to the dealer and my parts won't be here until tomorrow.

[brans72]

Tell us more!!!! Don't leave us hanging!!!!!

[Mike Norris]

I am sure bigtyme1 will chime in, but the way he has the hoses setup is that the ports on the back of both valve covers are tied together with a "T" and the run to the large vacuum port (for the brake booster) on the back of the intake with no PCV valve.

This setup would put quite a bit of vacuum on the crankcase and possibly a lot of oil into the intake. He is going to check the intake and see if this is so.

I am guessing if there is a bunch of oil in there he will have to redo everything to run a PCV valve setup, but this will require a different tune to recalibrate for the less amount of air drawn into the intake.

If there is no oil, he is going to try and run a PCV valve setup anyhow and see how she runs. If it is quite bad due to the tune being done for a non PCV setup at that point, he can go back to running it the same way with the exception of just pulling vacuum from the rear of the passenger valve cover only. Now this is not right in my opinion, but it will work for what he has if it ran well before.

Hope this helps and waiting here how it works out.

The LS vacuum, PCV and breather systems are very simple for sure, but can be easily setup wrong without a proper diagram or advise.

Mike Norris

[bigtyme1]

Mike, just realized you sell these catch can kits. Call you tomorrow.

Will your can fit between my head and AC compressor?

http://i941.photobucket.com/albums/ad251/bigtyme1/motorcover2.jpg

[Mike Norris]

I do not think it will fit there based on the picture, but it can mount about anywhere, be it on the engine in another location, the engine accessory brackets, inner fender area, firewall or even the core support.

Though it was originally built for the LS engines, it is a very universal unit. The bracket can spin 360* aorund the body, it can slide up and down the length of the body and it can be flipped over if need be. The hose length can be whatever it needs to be, as long as there are no large dips going to the can.

Just let me know and thanks.

Mike Norris

[bigtyme1]

Follow this link, I ended up doing this today. Get GM 12577927. Its a Internal PCV system with Oil Seperator for a LS6 motor. You can basically eliminate all the hoses on the top of the motor. http://www.ls1howto.com/index.php?article=18 The catch can is still probably a better idea for racing but I don't have the room to put it in.