Originally Posted by SpinMonster

Define worked.

To me the term 'worked' means that there is zero oil in your intake manifold. Is that what you are saying?

Originally Posted by glenB

The problem with this setup is that under WOT there is no vacuum and therefore no ventilation. So, not effective at WOT.

Originally Posted by Maui

I don't see the magic oil can on their website. Link please.

Originally Posted by Craigster05

I just noticed your post times....dont you guys sleep?

Originally Posted by glenB

I see it as two problems
1. Ring Seal
2. Block Ventilation

The first problem stems from CAFE standards required by the OEMs, in stock block applications. I believe Ford started it with their 5.0L engine back in the '80's when they reduced ring tension. Ford saw the error of their ways and increased the ring tension but still not as much as originally. GM followed suit in reducing ring tension.

This reduced ring tension increases the chances of blow-by which in turn increases the pressure in the crankcase. This pressure has to go somewhere.

The second is block ventilation. This is built into the design of the block. In the early years of the LS1 many Corvette owners complained of high oil consumption. GM determined drivers with the 6 speed was holding a low gear and keeping the revs up.

The design of the first LS blocks, the area between the mains was fairly isolated from each other and this was causing a large portion of the problem. When you have a crank, cam, rods, pistons etc rotating and oil dripping down from the top it beats the snot out of the oil and turns it to froth. GM's fix was to make the 'windows bigger' and the LS6 block was born. The LS2 was improved some more and the LS3 block has received more improvements in this area.

Professional race cars use dry sump systems to suck the oil/froth etc from the block, pass it thru an aerator and into an oil tank. The LS7 is a good example of this. It's all done to reduce parasitic drag on the rotating assy and to free up some horsepower.

When using dry sump systems there is a negative pressure in the block, this is to draw in the loose oil flying around and reduce the pressure on the back side of the ring. This helps reduce ring flutter at high RPM's which helps seal better which allows the engine builder to use less tension ... so it's an accumulative process in this aspect. It has been shown though that there is a line between too much and not enough.

If you go to your local circle track you will see in the lower classes that the engines have a tube connecting the two valve covers together, this is to reduce any oil from dripping on the headers from the filters to equalize the pressure between the two halves of the block.

Years ago in drag racing it was popular to use a 'pan evac' system which consisted of carefully placed tubes in each collector to draw a vacuum in the engine, via the valve covers. The problem with this is the tubes had to be in the right spot, right angle and have sufficient flow at WOT to draw a vacuum. When they worked, they did so only at WOT.

Then they went on to adapt AIR pumps to work as vacuum pumps but they were really troublesome. Moroso and others now make dedicated pumps for this. They are belt driven and can be adjusted for the vacuum level desired.

Because of the problems early on with the LS1 and continuing today, people have gone to installing a 'catch can' between the PCV valve and the vacuum source. This can has two chambers with a screen assy to separate the oil and air and in theory, and most applications, allowed no oil in the intake. The problem with this setup is that under WOT there is no vacuum and therefore no ventilation. So, not effective at WOT.

The system from Cartek, as described above, removes the vacuum altogether and only catches the oil pushed out by the crankcase pressure. Again, not effective unless your only desire is to eliminate the oil in the intake.

As HP goes up, in stock block applications, there tends to be more blow by because the rings are operating outside their intended application. It's nobodies fault, it just happens.

I believe the proper way is the same as in the past with AIR pumps, only using the current electric pumps with a catch can inline to separate the oil. This will allow a negative pressure in the block, with good ring seal, nearly all the time and isolates the oil from the intake. These pumps are less than $100 and the motors can be replaced separately.

Originally Posted by SpinMonster

Originally Posted by Bludog

Hey Spin, Can you post some photos? Getting ready to get a catch can, and now I am even more confused.

Originally Posted by Plano76vette

quick thought.

I do not think that there is anypoint to having the catch can, if you are going to just vent it to atmosphere. I say plug the lines and put a breather in the cap.

Nother thought, i think that the design of this engine pulls a large amount of vacume at WOT and that is why we are losing so much oil. I lost a quart and a half in about 1500 miles of driving it!!! I thought i hurt the engine, but i really think that this is the issue.

Also i thought that the main part of the PCV was to help clean the air in the crank case. Well all on the PCV systems were developed before synthetic oils, maybe synthetic oils do not have this problem?

Originally Posted by LSCHLEM

I have two vent lines that vent to atmosphere at the bottom of the car. Nothing elaborate needed. cafe