pcv removal / catch can?

[1fast97gsx]

I have heard of people replacing the pcv valve with a straight barb fitting to elliminate a little crankcase pressure. I was thinking about doing this and then capping off the nipple on the intake manifold. I was going to run the line from the barb fitting ( old pcv location ) to my catch can. I also have another line from the valve cover ( the nipple that points towards the passenger side ) going to the same 2 fitting catch can itself. Now I'm wondering ... will this cause too much pressure to build up inside the catch can or is all the gas just going to leave the barb fitting and go into the catch can, leave all the oil in the catch can, and exit through the other line back into the valve cover? Just want to make sure this is the correct way of doing it. ( reason for this is because under high boost on my old setup my dipstick always popped out and I started leaking through the oil cap as well ... only under high boost )

 

[OMN_DSM]

Does your catch can have a filter on top or anything? From the sounds of it you have a catch can that has one inlet adn one oulet and the out let is supposed to hook up to your intake pipe and the can is just there to catch the oil from entering the intake. It needs a way to vent.

Mike

 

[1fast97gsx]

Does your catch can have a filter on top or anything? From the sounds of it you have a catch can that has one inlet adn one oulet and the out let is supposed to hook up to your intake pipe and the can is just there to catch the oil from entering the intake. It needs a way to vent.

Mike

Yea that's what I was thinking as well. Would I be alright just to drill another hole in the catch can at the top, but another barb fitting on and run a hose from there to the ground? Thanks.

 

[OMN_DSM]

Anything to let some pressure out would be good, most catch cans just have like a little filter on the top to let the gases out. They look like the the ones found here http://roadraceengineering.com/eclintake.htm third item down on the page.

Mike

 

[jott5555]

do remember a majority of people who do this modification often have massive smokeing issues after

 

[sweet97]

I came over from the starquestclub and the ZConquests and Starions ran KrankVents to relieve crankase pressure, actually creating a vacuum so the piston/crank assembly actually would spin easier and make more power. No one here seems to use one, any reason why?

 

[dsmracer_1991]

sweet, is there any way to go more in depth about your post. i would love to know more.

 

[sweet97]

sweet, is there any way to go more in depth about your post. i would love to know more.

Give me some time tday to find some info on the product and a supplier. It is a device that removes crankcase pressure creatin a vacuum if i remember correctly. Eliminates the oil dip stick poppng out and adds a few ponies. mark

 

[BudmannG]

Here is the information you guys were needing.

These are the New Krank Vent Kits. They are the Smaller more suttle version which take less space and look really nice.
The Price is $99+$5 shipping

http://www.kdmperformance.com/

 

[95GSXBLUR]

Here is something else you all might be interested in:

http://dsm.dejonpowerhouse.com/

go there then to the bottom where is says BOV-MISC-TOOLs and click it on the left menu.. it's right at the top. kinda the same concept... $100 though.

 

[WatchItExplode]

Why are they so expensive? Looks like a very simple device.

So how does it work to create vacuum? If it's just a one way valve, it would seem like it would just vent all the pressure in the crankcase keeping it at atmospheric.

 

[420a16g]

does anyone have any pics of a catch can installed on a turbo'd car?? im still hella confused on how to hook mine up since the instructions are written completely in PHUCKING JAPANESE!!! any pics, instructions, walkthroughs, etc... would be extremely helpful.

 

[RedTurboEclipse]

I just leave the hose hanging.. I dont have any blowby though, I hope its ok.. those crankcase things that dejon sells is neat.. but seems too expensive for what they are.. Im sure someone can duplicate it with a trip to home depot

 

[Defiant]

Leave the PCV valve in place, and just run it to a catch can. Run the catch can outlet to ground or intake, your choice.

A hundred bucks for a couple of chromed check valves? I'm in the wrong business.

 

[MNGSX]

I would just get a npt nipple and install it in place of the PCV then route both to a catch can with a breather on it..


You could get a salvage yard electric vaccum pump and plumb both to it for less than those valves..

 

[BudmannG]

Here is a quote from the maker of these so called check valves.
Finally, these valves have never "failed" on a boosted engine except one - The 2nd stage NO2 valve stuck open w/ 20 lbs boost & blew the small KV + the engine, the hood off, both fenders off as well! We figure that the KV saw at least 2000 PSI as it was "gone" when the engine blew! We replaced it for the racer!
http://www.et-performance.com/
http://www.krankvent.com/
There are a couple of his web sites too. So I did research this very well. Now you guys can search it and research it also.

 

[4wd-Eclipse]

Looking for CHEAP vacuum check valve ... go to summitracing.com and search for " check valves"

 

[420a16g]

Leave the PCV valve in place, and just run it to a catch can. Run the catch can outlet to ground or intake, your choice.

A hundred bucks for a couple of chromed check valves? I'm in the wrong business.

FINALLY!!! someone gives me an answer to my question that i can understand. Thanx Defiant

 

[DSM4me44]

Hey check this out....

http://www.dsmtuners.com/forums/showthread.php?t=198301&highlight=crankcase+pressure

I also drew a diagram of my explanation and i can e-mail it to you upon request.

 

[oldman]

I have heard of people replacing the pcv valve with a straight barb fitting to elliminate a little crankcase pressure. I was thinking about doing this and then capping off the nipple on the intake manifold. I was going to run the line from the barb fitting ( old pcv location ) to my catch can. I also have another line from the valve cover ( the nipple that points towards the passenger side ) going to the same 2 fitting catch can itself. Now I'm wondering ... will this cause too much pressure to build up inside the catch can or is all the gas just going to leave the barb fitting and go into the catch can, leave all the oil in the catch can, and exit through the other line back into the valve cover? Just want to make sure this is the correct way of doing it. ( reason for this is because under high boost on my old setup my dipstick always popped out and I started leaking through the oil cap as well ... only under high boost )

Dipstick popping out and oil forced out of oil cap are usually indications of the following:

1. Excessive blow by from rings.

2. Leaky valve seals/guides.

3. Stuck open pcv valve.

4. Poor crankcase ventilation caused most likely by a stuck closed pcv valve or a full catch waiting to be emptied.

5. Combinations of 1-4.

On the subject of venting the crankcase, the best case scenario is the stock locations where you get a pull from turbo when under boost and from pcv when under vacuum. The worst case scenario is what you have described with an internal filtered catch can that loops back to the breather which will result in no ventilation period, you're simply just filtering out oil. If you decide to reroute both the pcv and breather to a catch you must do the following:

1. Hollow out the existing pcv or replace it with an 1/8 npt straight fitting.

2. Used an external filtered catch can.

3. Make sure the catch can is never full. Running hoses straight down instead of a catch can will remove this possible problem from the equation.

After a year of problems caused by a frozen catch can, a new turbo and a new head (valve seals) later, I have decided to run my pcv valve back to the intake manifold (make sure the OEM pcv is leak free) and install an internal filtered catch can on my breather valve to keep oil out of my IC. This is the best solution I came up with after some serious considerations.

 

[TSIfreek]

Bruce I have to disagree with you. Running a PCV will still put oil in the intake and I do not see any reason for running one. I have a JM fabrications catch can on mine and what I did is removed the fitting that goes to the intake manifold for the pcv (TUBE) and use that fitting in the valve cover (the threads are the same and is not a 1/8 NPT its metric and you cannot find it any were). I cut the tube off the pcv and stuck it in the intake and caped it off with a rubber plug and zip tie. I have both lines running to the catch off my valve cover. I did notice alot of excess gases coming out of the catch can filter and into the car giving me a headache but no smoke so what I did is instead of using the filter I ran a hose from the top of the catch can to the bottom of the car.
The best scenario would be to run the tube into the exhaust somehow to pull the gasses out of the motor more efficiently for better ring seal. You will get get gases coming out of the catch can on any motor pistons going up and down cause this to happen. More gases and oil will be seen in the can from a tired motor. I just check mine once a month and just very very little in there but thats on a new motor and its good to keep an eye on it. If you need a pic I can post it but its real simple.

 

[oldman]

Chris, I understand that routing the pcv back to the stock location will allow blow by in the intake manifold but that is something I'm willing to put up with to ensure what happen to me does not happen again (Believe me it was a tough decision, my intake manifold is ported/polished/pitted to my new fully ported head, never seen it so clean ever ), what concerns me more is coating my ic with oil. In speaking to my engine builder, also a wiseman on this site, he and I both agree routing pcv back to intake manifolds is the best arrangement. I'm sure VTA will work as well but call me paranoid, I refuse to take any chances (just for a clean intake manifold) after spending 4.5k+ on new parts.

 

[TSIfreek]

Bruce, please explain to me why you think a pcv is needed?? The only thing I know of how the PCV system works is by just allowing blowby gases back into the intake for emmissions reasons and has absoutly no effect on engine durability. If you want to run a pcv thats fine but the hose comming off the valve cover into the can needs to go back in the turbo intake tube or you will run lean at Idle and when ever the engine is under vacume and could have an effect on your fuel trims. Remember the pcv is open when ever under vacume. Just keep that in mind.
I dont arguee with any wiseman on here just adding comments that may help explain and help others view things in a diffrent way to understand.

 

[oldman]

Bruce, please explain to me why you think a pcv is needed?? The only thing I know of how the PCV system works is by just allowing blowby gases back into the intake for emmissions reasons and has absoutly no effect on engine durability.

Two reasons:
1. Like already mentioned above, better ventilation, a pull from turbo under boost and a pull from intake manifold under vacuum. Do I know for sure that this is much better than VTA or whether VTA alone is enough? NO, but like I said before, I'm not interested in finding out.

2. I do not trust myself in making sure that my catch can is functioning all the time (sometimes is out of my control like my last frozen filter) nor do I care for a dirty engine bay, a dirty IM I do not see and performance lost is minimal if any.

If you want to run a pcv thats fine but the hose comming off the valve cover into the can needs to go back in the turbo intake tube or you will run lean at Idle and when ever the engine is under vacume and could have an effect on your fuel trims.

I'm, hence the internal filtered catch can to keep oil out of my IC. You should only either VTA or re-route both back to stock location and not mix them.

I dont arguee with any wiseman on here just adding comments that may help explain and help others view things in a diffrent way to understand.

How dare you? Don't you know we're never wrong? Discussions are fine as long as it stays civil, especially on a subject that can probably go either way.

 

[GPTourer]

does anyone have any pics of a catch can installed on a turbo'd car??

The other end of the hose that is not visible goes under the can and attaches to the intake.