Valley cover

**sutie** · 02-23-2011, 05:33 AM

so i have two different part numbers for valley covers. one is Part number 12577927 for the engine block valley cover for the 2004 LS6 and LS1. and the other is Part number 12568002 for the engine block valley cover for the 2001-2003 LS6. are there any major differences in these covers? if so, which one do i need for my 99' LS1. *im fully aware that i have to do some modifications to the block to make it fit*

**brian r** · 02-23-2011, 06:59 AM

The 12577927 has the PCV valve built in so it is a simple tube from the valley to the intake. The other one still needs a valve. I just did the same thing on my 1998 and I used the 12577927 much cleaner!

**sutie** · 02-23-2011, 07:00 AM

good deal, thats what i was wondering! thanks

***SMWS6TA*** · 02-23-2011, 07:38 AM

Originally Posted by brian r

The 12577927 has the PCV valve built in so it is a simple tube from the valley to the intake. The other one still needs a valve. I just did the same thing on my 1998 and I used the 12577927 much cleaner!

Correct. Also just did the same thing.

I also recommend new knock sensors too.

**sjsingle1** · 02-23-2011, 12:57 PM

http://www.ls1.com/forums/showthread.php?t=145557

stikees are your friend :P

**sutie** · 02-24-2011, 05:07 AM

i just replaced the knock sensors, oil seals, wiring harness and valley cover gasket about 2 months ago, so all that should still be good, but when i take it apart, ill check it again of course.