I understand how you connected the can. I also understand the diff from the standard street can setup. your basically running an open system. The PCV valve is not required-I think? you have a catch can for overfilled valve covers.
the real fix sounds like oil control for high rpm applications.
a oil passage restictor or special pushrods with less oil flow.

Big block chrysler engines would pump way to much oil at high rpms to the top of the motor. the result was usually a spun bearing-bin there done that. oil restrictors and an 8 quart pan solved this.

 

You have some other issue... I run 4-6 HPDEs a year. I run an elite engineering catch can in the PCV line w/ my oem LS6 PCV system.

I catch maybe 1/4" of oil in the can a day at an HPDE. The fresh air line is dry and the oem valve cover is heavily baffled.

 

Compression and leak down tests are in order if the engine is getting that kind of blow by.

 

Oil in the catch can doesn't mean it's excessive blow by. If he has to much oil in the valvecovers it's going to get into his catch can since it's the only way for the blow by to escape during full throttle. I would be worried about starving the bottom end druing track days though and recomend he use the restricted pushrods. Was he running a stock engine or modded? He did say he didn't use much oil after the new setup though.

 

Or even taller valve covers.

 

 

OK rik, I replicated your setup on my vette. Drove around town below 3000 rpm and there was no oil in the can. Then I really drove the car around the parking lot where I work at. Sure enough there was oil in the can, about 1/16 of oil in the can about 15 min hard driving. I think that under high oil pressure, 40+ psi, alot of oil gets into the PCV tube leading out of the valve cover. The breather on top of the can starts to vent the PCV gas at idle. I don't know, but maybe the corvette valve covers have insufficient oil baffles for track use. I had the same problem on my mustang, I had to weld about 1" more material to make the baffle longer to reduce actual oil getting pass.

 

^ I have an LS4 oil pump that makes 49psi hot idle 55psi hot cruise and gets in the 70's at WOT when not on track. On track when oil is 250+ OP stays between 50-55.

I have no issues... Here's the Valve cover w/o stuff on it:


Here's a pic of the underside of the passenger side valve cover on a Z06:


That black plastic part is the baffle that doesn't let oil in the line... it may be that some of you have had that part fail.

Again... I have higher than stock oil pressure, I run HPDEs w/ my car (it's why I bought it), and I catch very little oil in my can at events. About the same amount as a few thousand miles of street use.

 

Maybe my oil baffles are failing. Rik should check his.

 

My baffles are fine. just had the valve cover off 2 weeks ago during a header install.

Why is it so hard for some to grasp the design issue with cars pushed HARD on track. Rev matching (i.e., heal-toe shifting) along with high g forces bring this design issue to light.

MANY people experience this issue with HARD track use.

People need to stop trying to diagnosis a problem with my car, there is no problem other than the design issue. This design "problem" is why GM redesigned the PCV system on the ZO6.

I wish some of the guys on here would read that I can drive 3,000 - 8,000 miles of VERY aggressive "country" (i.e., back roads) driving HAMMERING the car and not get any oil in the catch can. I also don't use any oil as per the dipstick during these AGGRESSIVE street miles.

ONLY ON THE TRACK DO I EXPERIENCE THIS ISSUE. DON'T YOU THINK IF THERE WAS A "PROBLEM" WITH MY CAR IT WOULD HAPPEN ON A REGULAR BASIS?

Rick

 

Rick... are you stupid? I track my car every few months. I have V710s on 17x11 GS wheels all around. I run an Ultrashield Pro Road Race seat. I trailer the car... I have an oil cooler, brake coolers etc etc etc.

I beat the **** out of my car normally shifting a few hundred rpms short of my 7000 rpm limiter.

I, and many others, DO NOT have oil usage in the manner you describe. T

There have been a handful, namely BQuicksilver, who have had crazy oil usage... but the vast majority do not.

My father has an '04 Z06 and my mother a '99 C5 and neither have issues like you have. My father's Z06 is also tracked... he has an EE catch can and gets about what I get out of mine.





^ That doesn't look like hard backroads driving... your car has something else going on with it I can take some serious G's with the wheel/tire/suspension/seat setup I run.

The Z06 PCV system, which I have, only moves the source of the crank ventilation to the valley area. The fresh air line from the valve cover to the TB is the exact same.

You are saying the oil is pushing back through the fresh air line. You need to tie your PCV lines (you have 2 w/ an LS1, one from each valve cover) into a catch can. You can put a breather oil cap on if you want.

If you do that you can remove the fresh air line and you will have everything accounted for, however, unless your baffles are messed up oil will not push up the fresh air line. If that is happening you will get oil in you intake tract too.

 

Interesting question. I guess I'll say yeah, I'm stupid...... Thank you for your continued interest in the well being of my car.


Rick


P.S. You also wrote:

Hmmmmm, tie PCV lines into catch can with a breather and remove fresh air line bypassing intake. What a great idea, but what a minute, let me think.....Oh yeah, now I remember.......I saw this somewhere before. Now I know where I've seen this solution, that's what I posted as having done to solve the issue in my very first post which started this thread.

If I wasn't so stupid I would have thought of this solution myself.....

Thanks for sharing your technical insight.


P.S.S.

You also provided:

No, that doesn't look like hard backroads driving. Those cars "look" real fast. To confirm all I have to do is ask you..... You "sound" real fast. Go Speed Racer!

Once again, THANKS!

 

If you've got both PCV lines going to the catch can and you're still filling it up each session you have issues. You can keep denying it, but it's not normal.

 

Go away boy, you bore me.....

 

It sounds like you've got both the PCV lines and fresh air lines going to the catch can.

What you should do is run the PCV line to the can and the other line back to the intake manifold, that way you can take advantage of the "positive" part of the equation.

Then completely cap your fresh air feed line and run a breather in the oil cap.

This way you should get no oil in the system... if it's still somehow forcing that much oil into the can, especially w/ your current setup that doesn't go back to the mainfod, then you've got some serious crank pressure and/or faulty oil baffles.

 

Your post insinuated that people giving you advice did not understand what they were talking about, that hard backroads driving wouldn't cut it, and the issues you're experiencing are normal/common in tracked cars.

They are not... PM Bquicksilver and see if his restricted pushrods worked for him.

 

This is exactly my experience. I have catch cans on both the PCV and Fresh Air lines.

The Can on the PCV line always catches some while the one on the Fresh Air line catches little. Go to the track and the Can (ELITE) on Fresh Air line is FULL after one session.

I will have to explore your setup. I was told that if you are getting fresh air that is unmetered (as your setup is) that your tuning will be off.


DH

 

The so called "popular" catch cans are not ment for "Endurance Racing"

Most all of the corvette owners that drive their cars on the street dont want to smell oil comming into the A/C and into the cabin and for their application a pcv can does keep about 70-75% of the oil out of the intake track .

Most all endurance racing applications would normaly call for a 1 quart breather can and depending on the horse power , a vacume pump would be inline with the breather can .

I fully understand gravity but 24 oz's in 70 miles is a good sign of lose rings under max stress .

You dont need a catch can , you need an over flow setup .

Do you think the C6Rs run for 24 hours straight losing 24 ounces in 70 miles ? , hehe