PVC system mods
Thread Starter
Pro
Joined: Sep 2014
Posts: 513
Likes: 11
From: Hills of Tennessee TN
PVC system mods
I am approaching a C5 tear down for heads and cam and ran across a suggestion for modifying the LS1 PVC to the LS6 style by changing to the LS6 valley cover.
The article I ran across said this "A PCV system is designed to force any positive crankcase pressure into the intake manifold, rather than continue allowing the engine to build up pressure inside. The LS1 system just happens to force oil along with the air as well, so GM seemed to take a stab at fixing the issue with the LS6 system. The LS6 setup pulls the pressure not from the valve cover, but from the VALLEY cover. This is the cover that resides under the intake manifold, and sits between the 2 cylinder heads."
So, opinions from those who may have observed or done this mod. Since I going into the engine anyway is the switch to the LS6 valley cover & LS6 PVC hose routing (less than $100.00) worth while or should I stick with the LS1 valley cover and a catch can. The car will be supercharged if that makes a difference.
The article I ran across said this "A PCV system is designed to force any positive crankcase pressure into the intake manifold, rather than continue allowing the engine to build up pressure inside. The LS1 system just happens to force oil along with the air as well, so GM seemed to take a stab at fixing the issue with the LS6 system. The LS6 setup pulls the pressure not from the valve cover, but from the VALLEY cover. This is the cover that resides under the intake manifold, and sits between the 2 cylinder heads."
So, opinions from those who may have observed or done this mod. Since I going into the engine anyway is the switch to the LS6 valley cover & LS6 PVC hose routing (less than $100.00) worth while or should I stick with the LS1 valley cover and a catch can. The car will be supercharged if that makes a difference.
Safety Car
Joined: Jan 2001
Posts: 4,990
Likes: 500
From: Hilton NY
I saw no difference on a '98 between the two systems you describe, both allowed oil to pool in the bottom of the intake manifold. The engine, now at 115,000 miles, never burned more than a half quart of oil in 10,000 miles. Adding a catch can did stop black soot spots from forming at the back of the car.
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Mine is a 98 with S/C and added a catch can way back before they became popular, first one I made myself and it worked quite well. 2nd one I bought has the same basic design just looks nicer.
Racer
Joined: Feb 2017
Posts: 317
Likes: 140
From: South Carolina
Sorry for the Necro-Bump but one thing I have seen often is people doing the LS6 valley cover mod on early engines but NOT CHANGING THEIR VALVE COVERS
The driver side cover on the non-LS6 Block cars have a fixed oriface tube which is basically just a small hole to draw from. This itself gets clogged or has buildup from the cover's baffles getting clogged so it's basically causing many engines to burn more oil & not properly ventilate. Changing to the later revisions and adding the inline PCV helps A LOT but also adding a catch can in a sealed system will nearly eliminate the oil into the intake but you will need to drain it out.
The driver side cover on the non-LS6 Block cars have a fixed oriface tube which is basically just a small hole to draw from. This itself gets clogged or has buildup from the cover's baffles getting clogged so it's basically causing many engines to burn more oil & not properly ventilate. Changing to the later revisions and adding the inline PCV helps A LOT but also adding a catch can in a sealed system will nearly eliminate the oil into the intake but you will need to drain it out.
Supporting Vendor
Joined: Aug 2013
Posts: 1,369
Likes: 294
From: Virginia
Sorry for the Necro-Bump but one thing I have seen often is people doing the LS6 valley cover mod on early engines but NOT CHANGING THEIR VALVE COVERS
The driver side cover on the non-LS6 Block cars have a fixed oriface tube which is basically just a small hole to draw from. This itself gets clogged or has buildup from the cover's baffles getting clogged so it's basically causing many engines to burn more oil & not properly ventilate. Changing to the later revisions and adding the inline PCV helps A LOT but also adding a catch can in a sealed system will nearly eliminate the oil into the intake but you will need to drain it out.
The driver side cover on the non-LS6 Block cars have a fixed oriface tube which is basically just a small hole to draw from. This itself gets clogged or has buildup from the cover's baffles getting clogged so it's basically causing many engines to burn more oil & not properly ventilate. Changing to the later revisions and adding the inline PCV helps A LOT but also adding a catch can in a sealed system will nearly eliminate the oil into the intake but you will need to drain it out.
