joseph143

iTrader: (8)

^ yep... i had a poor catch can setup and it pushed oil into the exhaust for me... smoked out quite a few intersection and a shop with a dyno because of it... burns that **** no problem...

Migsubishi

iTrader: (38)

Wow, I'd say you had to check your oil level often, mine doesn't push oil like that but there is traces of it. I'm going to cap my port at the back of the valve cover where the pvc used to be and just run the two side ports. I'll see how that goes for a while and if there is enough to drain I'll re-route it.

94AWDcoupe

iTrader: (125)

this is what I am talking about when I say you dont know how to think for yourself. this would be a pointless test. there may be pressure build up on the stock system because the stock vent is soooo tiny. but once you have a 5/8 hole for a vent there will be no pressure buildup any more.

its amazing to me you still "think" (because you theorize you do) you need your second can. you saw a drivability improvement because when you added your can you stopped oil movement into the combustion chamber. what you cant figure out in yourself is you will get same drivability improvement by eliminating PCV line/can altogether.

KISS notes fro anyone reading and very confused.
design a good size vent for your valve cover.
plug port on intake manifold which needs a PCV valve.

Dynotech Tuning

iTrader: (12)

The PCV system is designed to suck in FRESH air from the air intake system during vacuum (yes it 100% does). This removes harmful exhaust gas vapors from the crankcase, not only for emissions purposes but also to remove these gases so they do not contaminate the motor oil. These gases can break down the properties of motor oil very quickly, especially on a built engine with lots of blow-by.

Removing the PCV system to add extra ventilation at WOT isn't the best solution on a daily driver. You most definitely want to keep the PCV system in operation while trying to design an upgraded crankcase ventilation system for high boost applications.

-Jamie

94AWDcoupe

iTrader: (125)

I disagree with you . the factory PCV circulates a very small amount of air through the crankcase. it does not by any means keep combustion gases from contaminating the oil. virtually every molecule of air from combustion that passes through the crankcase will come in contact with oil.

pcv is a pollution device. read the wiki on pcv. its short and very precise.

Dynotech Tuning

iTrader: (12)

Then I guess we'll agree to disagree. I generally don't use "WIKI" as my source of facts.

You can search google for "PCV system oil contamination" and see if anything pops up. You might find a few reliable links.

-Jamie

94AWDcoupe

iTrader: (125)

I enjoyed the wiki read. I like the idea of using a road draft tube to evacuate case. gonna work on that for my needs.

I dont have any desire to learn more about pcv oil contamination. oil contamination in a 600hp car comes from boost blow by. no pcv system is going to lengthen the short oil change interval needed on a high performance turbocharged engine.

you can continue to promote pcv use as necessary. I feel its a waste of time.

tscompusa

iTrader: (31)

lol. i know the 5/8 hole is what eliminated all the crankcase issues and made the car improve in drivability. i never said it didn't.

i understand what you're saying. you say just cap the intake mani, eliminate the pcv and keep the setup as simple as possible with no check valve bs or any extra crap. not hard to understand.

i feel theres advantages in keeping the valve cover linked to the intake mani so it can move air into the intake mani. thats why my setup is the way it is.

maybe ill do some testing in the future to see how it is with just the intake mani plugged. in reality if i did that, i could remove the catch can system entirely.

<--------------------- lol

tscompusa

iTrader: (31)

What Jamie said is why i have it the way it is right now.

I think i'm going to cap the intake mani off after i get my car running again though

and see how it does with the simple setup. If no driveability changes or issues arise

then ill keep the intake mani capped off. i do like to keep stuff simple. the least amount of

things to fail the better.

03whitegsr

iTrader: (8)

Water vapor is a by product of combustion. The blow-by gases you speak of are made up of carbon-dioxide, hydrcarbons, and WATER VAPOR (along with some other oxides and nitrogen based by-products).

There is constantly water vapor in the crank case. By creating flow in the motor, you avoid condensation during operation. Granted, with the temperature a motor runs at, that condensation won't stick around long but in the case of high blow-by, I would bet you are creating a type of super-heated steam in the engine and condensation likely can take place on the walls of the block.

Creating flow in the motor allows the vapor to be removed under light throttle conditions, reducing the relative humidity in the engine and reducing the potential for condensation to take place.





Wrong.


I can agree here though. I use a VTA setup and dump it into a catch can that doesn't get drained back into the motor. It's simple and works without the need for check valves. As I said, it's not the ideal method, but it gets the job done. I have 5/8" lines as well. I did this setup a couple years ago and when I did it, I used both of the original vent holes, simply opening them up for 5/8" hose. After reading some of the newer posts here, I would probably stick to just one line off the side and just block the rear port.

240Z TwinTurbo

iTrader: (25)

I run the stock PCV on the intake and run a closed can between the valve cover and turbo inlet. I don't appear to have crankcase pressure issue running 36psi and my catch can yields almost no oil after a few months of running, just oil residue within the tubes. I have a slight hint of residue within the turbo inlet so the closed catch can is doing a decent job.

I would be hesitant to eliminate the intake PCV because the turbo does not create vacuum off boost so you have no way to evacuate the block. However, when cruising the intake is typically seeing 10InHg, which is a good source of vacuum to evacuate the block when the car is off boost. As long as the PCV valve is functioning properly I am not sure why you would remove. I would advocate a closed can between the intake manifold and PCV because my intake accumulates a decent amount of oil residue.

If your motor has a lot of blow-by you may want to consider using the exhaust to evacuate through a closed catch can. I have this setup on my car, but I have yet to try out. When I get time I will compare vacuum from the turbo inlet to vacuum from the exhaust.

http://www.verociousmotorsports.com/...-Vac-Scavenger

94AWDcoupe

iTrader: (125)

the valve cover has a baffle in it. the PCV in effect only circulates fresh air through the area contained in the baffle. the rest of engine case (which is 90% of the volume) does not get fresh air circulated through it at all. my points all remain solid. there is no real need for a PCV. the PCV eliminates water from baffle area faster, maybe, but it does nothing to keep the vapor from passing through crankcase. major condensation happens at start up. but that comes out my vent and is visibly gone after 5 minutes of running. my clear catch can is very clear on this. there is no visible vapor after 5 minutes run time and a tonne of vapor on start up.

94AWDcoupe

iTrader: (125)

using the exhaust to vacuum can has its own set of problems. years ago I was running a 2.5 inch exhaust on my 89 mirage. I wanted to relieve back pressure in the exhaust because I didnt want to custom build a second 3 inch exhaust. i drilled a 1" hole in the exhaust in about the cat position. i built a spring loaded flap for it that i though would stay closes at idle and light cruise, and then spring open under boost. Well just the opposite happened. that sucker was noisy at idle and cruise. flapping open and closed with exhaust pulses. it was dead quiet under boost. If you use exhaust to evacuate a sealed can it will only work under boost. drag car only mod. it will have pressure coming out at idle and cruise.

03whitegsr

iTrader: (8)

I seem to recall the inlet and outlet ports on the valve cover being seperate. Blowing air in one does not cause air to come out the other when it's not installed on the motor. The valve cover is designed to force fresh air into the cylinder head and then back out the PCV.

alexeiyreina

iTrader: (2)

Just get a good catch can from the head and from the bloc. Make sure its release pressure to the air