Check this catch can setup

Discuss the RB20, RB25 and RB26 series engines.
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Neejay
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Check this catch can setup

Postby Neejay » Mon Jan 05, 2009 7:35 am

NOTE: The picture is of a RB20 for those that can't see the RB20 on the timing cover



So basically:

old pcv valve location w/ installed adapter/port + driver's side valve cover -> T -> catch can port #1 / Catch can port #2 -> T -> [intake] + [inline PCV valve -> intake manifold]

Hopefully that's understandable. I want both the valve covers and the pcv sides filtered out. I was originally just going to have the valve covers T'd into a catch can and have the catch can going to the regular intake port.

Thoughts?


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Carl H
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Postby Carl H » Mon Jan 05, 2009 7:47 am

that would be the 'proper' way to install a catch can to ensure that it is under vaccum all the time and actually venting crank case pressure.

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Postby Coolwhip » Mon Jan 05, 2009 7:56 am

my head hurts just looking at that setup.

there is a way to simplify that system, while maintaning a proper setup

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Neejay
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Re: (Coolwhip)

Postby Neejay » Mon Jan 05, 2009 8:03 am

Coolwhip wrote:my head hurts just looking at that setup.

there is a way to simplify that system, while maintaning a proper setup
I wasn't able to find a more simple way, short of using 2 separate catch cans. This is from several hours of searching here and on skylinesaustralia.

If you know of a way, let me know. lol

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Postby Coolwhip » Mon Jan 05, 2009 8:07 am

drawing something up...

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mattblancarte
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Re: (Coolwhip)

Postby mattblancarte » Mon Jan 05, 2009 8:21 am

Is mine hurting my motor in any way? I just have one of the breather nipples open, venting to atmosphere from the catch can. Would there be any benefit to changing it? Sorry for the thread jack.


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Postby Coolwhip » Mon Jan 05, 2009 8:25 am

you have no vacuum drawing on the crankcase = incorrect

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mattblancarte
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Re: (Coolwhip)

Postby mattblancarte » Mon Jan 05, 2009 8:32 am

DOH! Should I run a t-line down to the capped valve? Will this change my current tune at all?

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Neejay
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Re: (mattblancarte)

Postby Neejay » Mon Jan 05, 2009 8:35 am

mattblancarte wrote:DOH! Should I run a t-line down to the capped valve? Will this change my current tune at all?
capped valve on the intake? yeah. It shouldn't change the tune since it's basically recycled air.

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Re: (Neejay)

Postby mattblancarte » Mon Jan 05, 2009 8:41 am

hmmm... perhaps I will do that this week. I have two lapping days coming up this weekend... so I'm a bit nervous of making any setup changes right now, though. It's been running perfectly in this setup for a long time now...

Is my current setup harming the motor, or can I get away with it as is?

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Re: (mattblancarte)

Postby Neejay » Mon Jan 05, 2009 8:46 am

mattblancarte wrote:hmmm... perhaps I will do that this week. I have two lapping days coming up this weekend... so I'm a bit nervous of making any setup changes right now, though. It's been running perfectly in this setup for a long time now...

Is my current setup harming the motor, or can I get away with it as is?
Well, it may not be "harming" the motor, but there aren't any scavenging on the crankcase with it like that...it's basically just leaking out of the valve covers, then getting filtered out very little, then vented to your engine bay.

There isn't any suction to actually PULL the vapor out of the crankcase.

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Re: (mattblancarte)

Postby Darius » Mon Jan 05, 2009 9:00 am

Although ugly, the Neejay's pic of a catch can setup works exactly as the stock system was intended to function.

Matt - your setup isn't "incorrect". It is providing a vent for the exhaust gases that pass by the rings and into the crank case. They travel thru the valve cover vents, into the catch can, and out the filter. Pressure relieved, works fine.

Pulling a vacuum on the catch can outlet is ideal for emissions and performance. And there are two ways to do this. One is to run a line from the catch can to the intake manifold (like stated above) and have a check valve in line so the turbo doesn't pressurize the catch can and crank case. When this is installed, you also need to run a line over to the intake pipe from the catch can. If you do not, then the turbo will spool, close the PCV check valve and effectively pressurize the crank case with blowby gases. BAD!

The second way is to run the valve cover vents to a catch can and then run a line from the catch can to the intake pipe. This way, it will always be under vacuum. However, this introduces oil vapors into the entire charge piping tract and lowers the octane value of the fuel. Not to mention it makes a mess of all the piping. BAD for blow thru MAF setups too.

I have mine vented to atmosphere like yours except I run a tube down below the frame rail and do not put a filter on it. My catch can filter clogged once and caused the engine to smoke like crazy. Looked like I was Spy Hunter.


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mattblancarte
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Re: (Darius)

Postby mattblancarte » Mon Jan 05, 2009 9:10 am

Darius wrote:I have mine vented to atmosphere like yours except I run a tube down below the frame rail and do not put a filter on it. My catch can filter clogged once and caused the engine to smoke like crazy. Looked like I was Spy Hunter.
Nice. I used to have mine vented to the ground out of the driver side fender.

Good call on the filter. I'll go run and grab another one this week... same time I get the beast wrapped in new shoes hehe.

Okay, glad I'm not going to blow up my motor. I was going to say, I've seen my type of catch routing done on a good number of cars...

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Neejay
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Re: (Darius)

Postby Neejay » Mon Jan 05, 2009 9:19 am

Darius wrote:Matt - your setup isn't "incorrect". It is providing a vent for the exhaust gases that pass by the rings and into the crank case. They travel thru the valve cover vents, into the catch can, and out the filter. Pressure relieved, works fine.

I have mine vented to atmosphere like yours except I run a tube down below the frame rail and do not put a filter on it. My catch can filter clogged once and caused the engine to smoke like crazy. Looked like I was Spy Hunter.
I've thought about doing this for simplicity and ease...

Also, did yours get clogged because you had the filter on the end? Like the oil build up finally clogged it?

I'm hoping my smoking problem is related to my pcv valve hose port being loose on the intake manifold and not my turbo...

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Re: (mattblancarte)

Postby gawdzilla » Mon Jan 05, 2009 9:20 am

mattblancarte wrote:
Nice. I used to have mine vented to the ground out of the driver side fender.

Good call on the filter. I'll go run and grab another one this week... same time I get the beast wrapped in new shoes hehe.

Okay, glad I'm not going to blow up my motor. I was going to say, I've seen my type of catch routing done on a good number of cars...
in theory the way you are running yours is not incorrect. that is conceptually how mine is run too. just venting to air.

in practice while on the track your filter looks way small so it might clog. your cabin will always stink of fuel/exhaust with it located there too.

have you tracked the car with that setup yet?

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Re: (Neejay)

Postby Darius » Mon Jan 05, 2009 9:25 am

Neejay wrote:Also, did yours get clogged because you had the filter on the end? Like the oil build up finally clogged it?
I had a filter on the catch can itself. I was out doing some tuning early one summer morning and it was cool/damp outside. I filled the catch can with water/oil vapors in a matter of 20 minutes. It was mostly water, but it must have soaked the breather filter and blocked the air flow off. Pulled over and popped it off and the smoking stopped. Since then I ran a line down low to keep the oil spray from covering the engine bay. Instead it will coat the bottom of the car in "rust proofer".

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Re: (gawdzilla)

Postby mattblancarte » Mon Jan 05, 2009 9:30 am

You're very correct in saying that it is a smelly experience. Luckily, my motor is very tight and runs like a beast. Just had it re-tuned at dyno-comp last week. Avg of 400whp on 100 octane and 15 psi.

I've tracked it 3 times, so a total of 240 minutes of hard driving. I've also driven it about 2000 miles with that filter and catch. Normally when people use clear tubes, they become saturated with oil. Mine almost look perfectly clear (that picture is after the third track day when I was cleaning the car), and I don't have a drop of oil in the catch. I love this motor.

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Re: (mattblancarte)

Postby zil40 » Mon Jan 05, 2009 9:49 am

you guys seriously have a vent line that goes from your catch can towards the underneath of your car? what happens if you crack a ring land and pressurize your crankcase, push oil out your catch can, with the vent located conveniently in front of your rear tires?

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Re: Check this catch can setup (Neejay)

Postby Neejay » Mon Jan 05, 2009 9:56 am

This also brings me to another questions: Are PCV sizes relative to engine size and/or the amount of vacuum potentially needed? I'm asking because to inline pcv valve that I'd have to buy is more skinny than the stock sized one.

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Re: Check this catch can setup (Neejay)

Postby Shocker » Mon Jan 05, 2009 10:22 am

My setup.

Red lines are the lines to/from catch can. Orange is the sealed catch can filled with steel wool. Bung welded on the intake for constant vacuum even under boost.


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Postby Coolwhip » Mon Jan 05, 2009 10:25 am

when i said incorrect, what i should of send was "not ideal".

Anyways, for all you track guys, does venting a catchcan to atmosphere pass tech?

Could see with those getting some nasty blow by from extreme pressure (and some of you clogging your drain to the ground) wouldn't that be unacceptable for track criteria?

I would like to repeat myself from previous discussion on this topic... check valve to Exhaust is the dopeness.

And those rubber hoses that you are running (though alot of kits include them) are horrible. I've had a SR melt one shut and caused all kinds of problems.

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Re: Check this catch can setup (Shocker)

Postby Neejay » Mon Jan 05, 2009 10:27 am

Shocker wrote:My setup.

Red lines are the lines to/from catch can. Orange is the sealed catch can filled with steel wool. Bung welded on the intake for constant vacuum even under boost.
Yeah, that's how I was going to run mine at first: valve covers -> T -> catch can / catch can -> intake

But I want the PCV valve to be filtered too...but if the valve covers are setup this way, is the PCV valve filtering even needed?

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Re: (zil40)

Postby Darius » Mon Jan 05, 2009 10:36 am

zil40 wrote:you guys seriously have a vent line that goes from your catch can towards the underneath of your car? what happens if you crack a ring land and pressurize your crankcase, push oil out your catch can, with the vent located conveniently in front of your rear tires?
Stop being paranoid. The outlet lightly puffs air that has some oil vapor in it. It doesn't lay down an Exxon Valdez oil slick....

Neejay - You can block off the PCV valve if that is how you want to setup the catch can. In theory, the catch can should remove the oil vapor before going into the intake, but it won't work that well unless you add a fill material like steel wool for the oil particles to stick onto.

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Re: (Coolwhip)

Postby mattblancarte » Mon Jan 05, 2009 10:43 am

Coolwhip wrote:Anyways, for all you track guys, does venting a catchcan to atmosphere pass tech?

Could see with those getting some nasty blow by from extreme pressure (and some of you clogging your drain to the ground) wouldn't that be unacceptable for track criteria?
I actually did my oil catch setup because when I bought the car, it was venting to the fender without a filter or catch. NASA requires that you run a catch can **with a filter** if you vent to atmosphere. So I did what you saw in the pic.

If you vented to atmosphere onto the ground at the track, you'd just be a jerk.
Coolwhip wrote:I would like to repeat myself from previous discussion on this topic... check valve to Exhaust is the dopeness.
Indeed. I've seen the supra guys do this a lot. I hear that if you're running lots of hp, it can actually see you some extra power gains.

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Neejay
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Re: (Darius)

Postby Neejay » Mon Jan 05, 2009 10:47 am

Darius wrote:
Stop being paranoid. The outlet lightly puffs air that has some oil vapor in it. It doesn't lay down an Exxon Valdez oil slick....

Neejay - You can block off the PCV valve if that is how you want to setup the catch can. In theory, the catch can should remove the oil vapor before going into the intake, but it won't work that well unless you add a fill material like steel wool for the oil particles to stick onto.
I'm actually going to use the stainless steel pot scrubber pads as I did with my catch can setup on my KA.

hmm...I may just have to do this then, because my pcv valve hose port is loose/out. Any negatives to doing it this way permanently?

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Re: (Neejay)

Postby zerodameaon » Mon Jan 05, 2009 11:09 am

I run mine vented also. i dident want those fumes going back into the intake. i run a second line off the catch can that goes down low in the engine bay so that the fumes get sucked out of the car due to vacume. i was getting sick every time i rolled down my windows.

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Postby gawdzilla » Mon Jan 05, 2009 11:12 am

^^ i relocated my catch can to sit next to my air filter. just having the 2 filters sit next to each other helps the engine consume a lot of the smell, while separating the oil out into the catch can.

Matt - that's kind of strange that you have no oil whatsoever in your tubes or catch can. there should at least be moisture in there. but it sounds like you have a setup that is definitely working if it's been track tested.


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Re: (gawdzilla)

Postby mattblancarte » Mon Jan 05, 2009 11:29 am

I definitely get vapor that comes through the catch, but there is BARELY any oil. The tubes have retained a little bit of oil residue, but you have to look closely to see it. I'm also not boosting too hardcore, so I haven't gotten to this point. lol


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Re: (Darius)

Postby zil40 » Mon Jan 05, 2009 11:48 am

Darius wrote:
I had a filter on the catch can itself. I was out doing some tuning early one summer morning and it was cool/damp outside. I filled the catch can with water/oil vapors in a matter of 20 minutes. It was mostly water, but it must have soaked the breather filter and blocked the air flow off. Pulled over and popped it off and the smoking stopped. Since then I ran a line down low to keep the oil spray from covering the engine bay. Instead it will coat the bottom of the car in "rust proofer".
"lightly puffs air with oil vapor"? i guess thats the "oil spray" thats coating your car in "rust proofer" and this is on a car that doesn't have any kind of engine failure. i'm saying it isn't very safe. if you don't care about "oil spray" coating the road in front of your rear tires then good for you. i don't think anybody should vent that underneath your car. thats all. your problem.

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Re: (zil40)

Postby Darius » Mon Jan 05, 2009 12:28 pm

Since you have no idea about my setup, the status of my engine, or the specifics of where my catch can outlet is, I will refrain from responding to your newb comments about "engine failure" causing a situation that "isn't very safe" by "coating the road in front of (my) rear tires".


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