is this LS6 intake? *pics*
And DEFINITELY get the 04+ LS6 Valley cover!!
R6cowboy, no LS1s in Fbodys came with the LS6 valley cover factory. The 04+ LS6 VC is the best also, due to its redesign. 01+s only have the LS6 intake, not the valley cover.
All LS1s including the 2001+ LS6 intake manifold ones have the old style cover with nothing built into it. The pcv valve is an external piece
See my post #10 above pic
All LS1s including the 2001+ LS6 intake manifold ones have the old style cover with nothing built into it. The pcv valve is an external piece
01/02 cars come with LS6 coolant lines since they are equipped with the LS6 intake manifold..
And DEFINITELY get the 04+ LS6 Valley cover!!
R6cowboy, no LS1s in Fbodys came with the LS6 valley cover factory. The 04+ LS6 VC is the best also, due to its redesign. 01+s only have the LS6 intake, not the valley cover.
All LS1s including the 2001+ LS6 intake manifold ones have the old style cover with nothing built into it. The pcv valve is an external piece
You're right, the 2004 valley cover GM# 12568002 has an oil seperater, and an external pcv valve is still needed.
But the 2004+ unit GM# 12577927 has a built in 2.5mm orifice pcv valve instead of baffles. it doesn't need another pcv valve.
GM even sells a u shaped hose GM# 12594779 that goes from the valley cover hose fitting to the intake manifold

This is the same 2002 TSB pcv valve design that was used as a fix for oil consumption, it replaced the spring and ball pvc in trucks etc.
Last edited by jg rider; Jun 14, 2011 at 09:31 PM.
The Best V8 Stories One Small Block at Time
I'm sorry for the confusion, John
Now I'll go hide in the corner You're right, the 2004 valley cover GM# 12568002 has an oil seperater, and an external pcv valve is still needed.
But the 2004+ unit GM# 12577927 has a built in 2.5mm orifice pcv valve instead of baffles. it doesn't need another pcv valve.
Last edited by HoLLo; Jun 14, 2011 at 11:07 PM.
01-03,04-11 who cares. I read somewhere that the improved version came out sometime in 04. The point is that there were two versions, one that had baffles but required an external pcv valve, and a newer version that had the pcv built in. That's all I've been saying
Now you can have the last word
Last edited by jg rider; Jun 15, 2011 at 12:43 AM.
01-03,04-11 who cares. I read somewhere that the improved version came out sometime in 04. The point is that there were two versions, one that had baffles but required an external pcv valve, and a newer version that had the pcv built in. That's all I've been saying
Now you can have the last word
My intent was to ensure any readers have the right information... I'm just trying to clarify the differences for everyone to know.. I'll be glad to have the last word, as long as things end up correct. Don't take it personal dude.... I'm using the newer 04+ version that has the built in improved PCV valve GM# 1257927.
I'm real happy with it as it helps clean up the engine because the pcv hose from the driver's side valve cover, around the back of the motor to the pass. side valve cover, and to the pcv valve can be removed.
You'll also need a valve cover plug GM# 12568011 for where the pcv hose is removed on the driver's side vc.
And a 3/8" vacuum cap to cover the the pass. side valve cover fitting.
If you intend to run directly the the intake and the intake's vacuum fitting is in the same location as on the stock manifold, you can get this hose GM#12594779 (see above pictures)
Or you can do as I did and run in and out of a catch can


Personally, other than a neater engine I'm not seeing any improvement in blow by. I have very little of it. That's probably because my car has only 29,000 mile on it and the rings are pretty tight, so not too much combustion chamber gases are getting past them.
Oh! Almost forgot. If this is going on an LS1 motor there's a little bit of cutting to be done on the block. Nothing serious
Here's a good write up on how to do it with a 04+ cover
http://www.ls1.com/forums/showthread.php?t=145557
And an older one, using the pre 04+ cover
http://www.ls1howto.com/index.php?article=18
Last edited by jg rider; Jun 15, 2011 at 02:13 PM.
Floorman- I'd say 04+, theres less hoses and less of a mess to deal with. And not to mention it helps the crankcase breathe a little easier and less chance of oil consumption.





