Vettechris996

Anyone using one of these in place of the clean-air line between the passenger side valve cover and the throttle body?

http://www.eliteengineeringusa.com/c...oil-separator/

Seems like it would help solve the oil ingestion issue. I already have their catch can on the PCV line but I still get some oil in the intake during high rpm on/off throttle situation.

Any experience?

Level8Drummer

Did you try this? What did you discover?

Vettechris996

I haven't yet bought one. Thinking I will though. Seems like a clean solution, just need to actually order it!

383

so its just a second catch can?

Vettechris996

Sort of. Looks to me like it replaces the oil fill cap and catches any oil vapor that would come from the valve cover to the throttle body and causes it to condense then drip back into the valve cover. Keeping it out of the throttle body and eliminating the need to keep emptying a can.

froggy47

Chevy has an OEM VENTED oil fill cap for about 5 bucks, vents under certain pressure as I understand it. Does not come on Corvette but comes on some other Chevy.

I stuck one on my 2004 z06 just for the hell of it.

Would that fit your scenario?

Vettechris996

I don't think so actually. You still want to have the fresh air line in place in that case since it sounds like a one-way valve. Plus, it could allow oil vapor to spew out in high rpm situations and make a mess under the hood. At least as I understand it anyway. Worst my car seemed to have it happen was actually 2nd gear on the Tail of the Dragon. Road course and autox don't seem as bad, or maybe its just there's no one there to notice!

froggy47

My actual experience (at frequent high rpm events) is this never happens.




Anyway, never mind, just trying to help actual real world facts.

Let us know what you end up with.

COSPEED

This is similar to the GM 1LE performance cleanside separator that is sold for just that, when you are in acceleration, their is no intake manifold vacuum present to maintain crankcase evacuation, so pressure will then build, and seek the path of least resistance, which is back flowing "out the in" or out the fresh, or cleanside of the PCV system. The Elite billet unit is app 1/2 the price of the plastic GM unit, and the GM unit is just an empty plastic chamber and the Elite has coalescing media in it to trap and hold the oil until vacuum returns to the crankcase and flow again runs in the correct direction. If you put an open breather on, then you are drawing in non MAF metered air and your tune goes nuts trying to adapt to the out of parameter data the PCM receives. So NEVER vent to the air.

The best is to install Elites Dual Valve E2-X system with cleanside just for those that drive hard. The secondary outlet takes over when the primary valve detects no vacuum suction and automatically switches to the suction present upstream of the throttle body where there is strong suction at WOT (the IM has none due to the over lap caused reversion spikes entering the plenum. They won't reach past the TB until over 8k RPM's or more) so no matter how you drive, the crankcase is always receiving suction and evacuation and prevents pressure from ever building (as long as you have no piston ring/cylinder seal issues) so it provides the next best thing to a belt driven vacuum pump.

Retains emissions compliance, maintains 100% MAF metered incoming air, and does not affect warranty.

So yes, great addition, and if you install the entire system (We have the Colorado Speed version as well in stock) you will not believe how well it addresses these issues. You should also realize better fuel economy, less over heating, and slightly more power as the oil ingestion is causing detonation and the PCM is pulling timing (causing less power and greater engine heat). And then the obvious, anything other than air/fuel in the combustion chamber reduces the usable octane as well as disrupts the burn and flame front and less energy is released per combustion (explosive event).

froggy47

The one I put on (if you are referring to that) only vents pressure (one way) so not sure how it would let in unmetered air.

Even if it failed the unmetered air would go to the crankcase, right? How would that effect the tune?

If you are referring to a full open breather, never mind, I have no experience with that.

COSPEED

If your venting pressure out, the PCM measures all incoming air, and the PCM has pre-programmed parameters for blow-by as well depending on RPM's, etc. So when you vent out several things occur. First, air that the PCM assumes is being eventually part of the intake air charge so it is commanding short term fuel trims based upon this data. When you vent some of this, the PCM expects this air is entering the combustion chamber so your fuel trims are going to hunt (add/subtract) fuel rapidly trying to balance the data it receives from the MAF, MAO, and up stream O2's. Now if you have a Speed Density tune this does not apply, but most NA builds are MAF tuned.

The next thing your doing is allowing pressure to build in the crankcase prior to venting, and this causes ring flutter, which compounds your blow-by and is immediately less power produced, and long term wears "divots" into the cylinder wall as well as the edges from the rings making them less able to seal properly and do their job.

Then your dealing with down stroke resistance as the pistons fight that pressure. This is parasitic loss of power as well.

By installing a system that pulls vacuum/suction at all times you avoid all of this, the proper system maintains a closed Emissions compliant system and traps all of the oil mist you don't want present in the A/F mixture.

Hope that helps!

froggy47

Yes that helps & your probably right on all counts, but, the engine runs like a beast (for a stock engine) the tune was done with the "special cap" on, no codes, no issues, minor oiling at the tb. No oil blowing under the hood. My guess is that venting at the oil filler cap is probably rare and minor.

Nonetheless thanks again for the post.



The other thing (in Kalifornia) is these can systems fail VISUAL emissions test so must be removed & reinstalled every smog test. The cap I use looks the same as the original one.

jstout

If the catch can has a breather on it, is it necessary to plum back to the throttle body? If so, what purpose does that serve? This is on a c5 road racing car, not street legal. Jerry

COSPEED

I imagine your tuner has compensated for the un-metered air. Heck, look at stock cars. Do you have one of the "checkvalved caps" that only allow a certain amount of air in and no venting by chance?

In many classes you cannot run any crankcase evacuation and only breathers and they make power like crazy withing tech specs. They change oil every race to keep the engine alive though.

Excellent post.

A breather type can/tank is not a proper system for correct fuel trims, etc. but you may be running a speed density tune and then the MAF does not come into play. The issue with a breatherd system, especially on a road race application is any time your accelerating there is no vacuum pulled on the crankcase so you are allowing pressure to first build and then vent out the breather. It is far better on the engine to avoid the ring flutter and other issues by running a system with dual evacuation suction sources so you never have pressure build in the first place. Keeps ring seal better, etc.

Here is a good video to watch to show the power effects of ring seal aided by pulling vacuum/suction VS venting. Long term is the wear to the rings and cylinder walls, but this demonstrates why never allowing pressure to build in the first place is always best. And both the Elite and the Colorado Speed systems provide for this as the next best thing for the street:

froggy47

That's an interesting video & goes to your point, however on a stock ls6 I imagine the difference with/without vacuum on the crank case is less. I don't recall the specifications of the oil filler cap or even if there are specifications available from GM, they are so forthcoming with information, haha.

I do know it's a stock cap designed for some pressure venting on one/some gm engines. Might have been for cold weather operation, I recall something about that. I just stuck it on to make sure crankcase wasn't pressurized as I had a front seal leak. Leak turned out to just be the shi&&y stock balancer which I replaced with ATI.

Never have had mine dyno'd, tuner used logs I provided, happy with all.

jstout

I am sorry to be dense on this, but I am a driver and business guy, not a motor guy. I race my c5 in NASA ST2. The original set up on this car when I bought it was both valve covers with hoses to a 350 ML catch can. The engine must be getting tired, because the blow by has started filling the catch can completely to the top, where it begins putting oil into my intake, fouling the plugs, engine missing and stumbling, loss of power, etc in the middle of the race until the end. It runs fairly strong till the catch can fills up. I figured I would put a bigger catch can on it with a breather on top of the catch can, and not run a hose back to the intake so no blow by product would be introduced into the engine.

I am gathering from this discussion that my idea isn't the way to go. Can you explain for me one more time why that won't work well? Thanks for your patience. Jerry

383

From what I gather, your fuel trims will be off by about 0.001% so you should retune for the breather...
Seriously though if you're filling a CC in 1/2 a race there are other things for you to worry about.

jstout

Understand other things to be worried about. Have one more race this season in about 25 days. Just trying to make it through before refreshing the engine. Thought this might get me by. ON a stock C5 computer, will .001% represent enough of a tune issue to feel it at the track> Thanks for the help. Jerry

Joshboody

Froggy, I think a vent cap is a great idea. Do you have the GM part#?

I've been thinking of a catch can, but any additional routing/cans will increase CC pressure... which I think is more important than intake oil vapor, especially when tracking.

aaronc7

I like the idea of this as well. Just the fact that the venting will be higher than the original valvecover outlet is a plus and I'm sure it has some baffling in there. I know some guys get oil pooling in the passenger side valvecover from long high G left turns, then when they get back on the gas, it get sucked right up into the engine thru that line.

I think I found the part number for the 1LE oil separator as mentioned above. I'm also a bit disturbed by the price. I am looking to see if there's a cheaper option that only includes the oil filler neck/cap.

12653073

http://paceperformance.com/i-1080525...ve-system.html