Ok i just received a new LS6 valley cover or so I thought. I have now learned that GM actually has 2 versions of this valley cover, or so I have heard. Can someone that actually know for sure the difference between the 2please chime in. The P/N that I was told to order is 12575742 Below is a picture of the one that I received. Is this the correct one or not, if not please let me know what the correct one is, along with any other parts that I may need to purchase to make it work correctly and look correctly.
Thanks,
Eric

 

That's a regular ls1 valley you have


You want the 12577927

 

Yep, that is a stock LS1 replacement. What you want is the 04+ LS6 version which is the part number mentioned before. Scoggin Dickey has them for just under $100.

https://sdparts.com/details/gm-facto...parts/12577927


It will look like this:

 

04+ LS6 actually looks like this:


The one you posted in the picture is an earlier LS6 that still requires a PCV valve.

 

Darn it just my luck!!! What else parts are needed to make this work correctly on my car?

Thanks for all of your help guys

 

Doh! Right you are. Should still be the correct part number however.

 

That link to SDPC should come with everything you need to make the swap other than a small piece of 3/8" SAE30R6 hose which you can pick up at a local auto store. The only obstacle if you have an LS1 block would be that you need to cut a small piece out of the valley to make it fit.

 

Yes, make sure you cover up the exposed areas because any debris that land in will cause some pain!

 

I just ordered the newer version from the local "stealership". Got a reply that the "system" had no parts in stock. He evidently found one thru some other method. Supposed to pick it up today. We'll see.

 

what are the advantages of switching to the 04+ valley cover?

 

No need for an external PCV valve and little to no oil in your TB & Intake anymore. Plus it cleans up the engine some by taking about 4-5 foot of hose and turning it into 6-8 inches of hose.

 

With the LS6 valley cover:

you will need to plug the PCV outlets on the rear of your valve covers (and remove the plumbing);

you will need the short u-shaped hose to go from LS6 valley cover outlet to intake manifold PCV inlet;

you still need the short hose from the throttle body to the passenger side valve cover.

 

Got the cover. The pt # is the posted # 12577927, and matches the 2nd pic.
$86.64.

 

I would still run a catch can i got the ls6 valley cover and still getting oil in my catch can. Alot less oil in catch can though. I got the 04 to 06 version.

 

mine looks like post #3. Is that the 04+?

 

Nope.

 

Post #4.

 

Hmm thats weird. I dont have a pcv valve on mine anymore. Just whats under the valley cover. And the little tube with the red cap that sticks out is routed into the manifold.

 

Hose routing is the same. You are just running a pcv system with zero restriction basically using an early LS6 valley without an external pcv valve inline with your hose from valley>intake. Getting oil inside your intake still? Try a PCV in line. If not you can just leave it.

 

This is correct, it will not eliminate it but it will help a bunch. Also, buy the GM U-shaped hose, it is a super tight bend and trying to make a straight hose work will not look near as good as their molded piece. Trust me I tried.