ls1 to ls2 swap.vac port.

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Mar 16, 2008 | 03:12 PM

blue99ta402

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From: Rapid City SD

ls1 to ls2 swap.vac port.

ok I have done a ls1 to ls2 swap and I have a vac, port on the front vally cover that the old one did not come with. What should I run this to if anything? It has a red vac, cap over it now.I can get a pic to show more detail.

Mar 16, 2008 | 05:49 PM

HSV-GTS-300

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From: Perth, Australia

The tube coming out of the valley cover is the stale air exit from the crankcase. On a complete stock LS2 a small U shaped hose goes on this tube and goes up and back into the side of the intake manifold.

The only other part to complete the PCV system is a "Fresh air tube" which takes fresh filtered air from in front of the throttle blade (attaches to intake pipe on factory LS2 cars, or to the throttle body air out port if using a cable pull type TB)....to the front passenger side valve cover. All other valve cover outlets are blanked.

Mar 16, 2008 | 06:16 PM

blue99ta402

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Staging Lane

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From: Rapid City SD

Ok it's the one up front with the black cap on it by the water pump that says stale air out.. I have nothing hooked to this, it's caped off. should I uncap it? or run a hose to it?
Thanks for the reply great photos!

sorry I just read it better thank you very much!

Last edited by blue99ta402; Mar 16, 2008 at 06:17 PM. Reason: didn't read good enough.

Mar 16, 2008 | 07:23 PM

Rare99Z

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From: Mokena, IL

wait, so what do you do if you are not using a LS2 intake manifold, just cap it off on the valley cover?

Mar 16, 2008 | 07:29 PM

HSV-GTS-300

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Quote:

Originally Posted by Rare99Z

wait, so what do you do if you are not using a LS2 intake manifold, just cap it off on the valley cover?

Noooo you run the hose from the valley nipple into the side of whatever intake manifold you are using.

Mar 17, 2008 | 10:30 AM

blue99ta402

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Staging Lane

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From: Rapid City SD

Ok I took a pic of what i have there is a hose hooked up to that port that looks like the pcv valve. Is this where i should run it? and if so where should I run the pcv valve?
http://img183.imageshack.us/my.php?image=img3458um1.jpg

Mar 17, 2008 | 03:15 PM

HSV-GTS-300

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Quote:

Originally Posted by blue99ta402

Yes that's the old LS1 PCV valve. You don't need it....you have a new LS2 PCV valve built into the underneath of the LS2 valley plate.

Pull the old LS1 PCV system off (It's probably old and deteriorated...prone to cracking and leaks by now anyway). This will expose the nipple on the side of the intake manifold where you need to run the new U shaped hose to.

Continue pulling the old LS1 hoses off at the rear of the engine on both sides. Throw the old oily octopus of LS1 hoses and PCV valve away.
Blank off the nipple at the rear of each valve cover.

[I run an LS6 intake on my LS2 and have done this to mine...2 1/2 years no drama]

You'll end up with:
1 hose going from the Air Out port on your throttle body....to the front passenger side valve cover. This is the fresh air tube.

1 U shaped hose from the valley cover to the side of the intake manifold. This is the stale air tube.

Both rear valve cover nipples blanked off.

= LS2 PCV system