Catch Can Help

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YBLEGAL

Regular Member w/ Cheese
Ok so I recently cleaned my intake manifold really good. It was filthy to say the least. So I'd like to prevent that from happening again. I've been researching catch can systems but I'm still a little unsure. So before I start hooking up vacuum to the wrong stuff or something, I'm asking for the help of HS to approve my design.

Concerning my B16 btw.

I've come up with a dual catch can arrangement. One of the catch cans has a filter breather on top and will have only the hose from the stock valve cover port going to it for catch during WOT. The other catch can will have a hose from the crankcase vent port on the block and a hose to the intake with a pcv check valve in line to provide savaging during part throttle and idle. Both cans will have baffles. Just didn't draw them.

Will it work?

catchcan1.jpg


Thanks for any input
 
You're not gonna need to add a pcv valve in line for the hose going to the intake manifold. The catch can pretty much takes over the job the pcv does anyway.

The line to the valve cover isn't gonna work it's best. That line needs vacuum to suck out any blow by.

I would ditch the breather filter and just run a vacuum line there and T it to your other vacuum line source that you already have for the block.
 
You're not gonna need to add a pcv valve in line for the hose going to the intake manifold. The catch can pretty much takes over the job the pcv does anyway.

The line to the valve cover isn't gonna work it's best. That line needs vacuum to suck out any blow by.

I would ditch the breather filter and just run a vacuum line there and T it to your other vacuum line source that you already have for the block.

I'm not intending an argument, but from what I've read, I do need a check valve on what ever line is providing vacuum to prevent boost pressure from entering the catch can and thus the crank case vent.

I also read the line on the valve cover sucks air into the valve cover when the intake manifold is in vacuum. When WOT or boost had achieved 0 vacuum in the manifold is when the natural low positive pressure of the blow by gas vents out of the valve cover.

My friend tried the T like your talking about and it sucked up a ton of his oil.

I'd like some other people's input as well. One of the reasons I'm unsure is because it seems like there could be lots of mis-information floating around. This is what I found to be the most accurate so far.
 
I'm not intending an argument, but from what I've read, I do need a check valve on what ever line is providing vacuum to prevent boost pressure from entering the catch can and thus the crank case vent.

I also read the line on the valve cover sucks air into the valve cover when the intake manifold is in vacuum. When WOT or boost had achieved 0 vacuum in the manifold is when the natural low positive pressure of the blow by gas vents out of the valve cover.

My friend tried the T like your talking about and it sucked up a ton of his oil.

I'd like some other people's input as well. One of the reasons I'm unsure is because it seems like there could be lots of mis-information floating around. This is what I found to be the most accurate so far.
i didn't know you were boosting. In that case then yeah, you'd need a check valve. And since you're boosting, you wouldn't want that line going to the valve cover. Should have stated you were boosting... check out these set ups Honda-Tech.com: Welding/Fabrication: Vented Valve Cover Post up some pics!
 
I'm not boosting at the moment. I will be real soon though, that's why I've done so much other stuff recently.

I've seen that thread and read it and some of that attributes to my uneasiness.

Have you put a catch can or dual catch can setup on anything yourself B16RacerN2NR?
 
So ok no responses.

Lets see, what your saying is have both the valve cover vent and the crank case vent go to the same catch can with vacuum on both? Does air not need to get into either? I was under the impression at any given time one must suck and one must blow, and at 0 manifold vac or higher the crank vent will be shut and the valve cover will vent positive. But regardless of boosting or not, lets just say I have an electric vac source, both crankcase and valve cover should be venting positivly outward under vac?

I just really need solid clarification...

Maybe how it works, not just how to hook it up :)
 
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I'm not boosting at the moment. I will be real soon though, that's why I've done so much other stuff recently.

I've seen that thread and read it and some of that attributes to my uneasiness.

Have you put a catch can or dual catch can setup on anything yourself B16RacerN2NR?
yeah, i've installed a catch can on boosted motors but just a single catch can.

I did them like this Oil catch can Install - Honda, Acura Tech Website, tutorials, tuning and HOW-TO's. Drag racing, street racing, road racing - C-speedracing.com
 
ok i have some questions regarding the catch can..so my ls has the pcv on the back off the block..i just run a line from that to the can,and then from the can back to the original spot on the manifold??should i use a closed can or a can with a filter on top?
and has anyone ever vented a valve cover??
 
I'm still trying to figure out how I'm doing it as well.

From what I can tell, ideally you want a vacuum on the crank case vent at all times, and the valve cover vent would pull fresh air in. But since with the natural function of a motor, we don't have constant vacuum in one area, and we generally don't use an electric static vacuum source, we have to accommodate for the 2 instances of vacuum. Vacuum present in the intake manifold at one time, and vacuum via Bernoulli effect from the turbo inducer or exhaust system at another time. If you do not have 2, and only use the stock system's default 1 vacuum source, at the intake manifold, when that vacuum source disappears, the natural pressure in the crank case builds up, and via the PCV check valve, will remain blocked in the crank case until it finds its way up the oil passages and into the valve cover where the natural pressure alleviates itself out of the motor.

If I'm right, then just run a closed catch off the crank case vent with vacuum on the catch can from the intake manifold. Then run the valve cover vent line to either your intake charge, a breathable catch can, or a hose to the ground, or a vacuum source you can figure out, like taping it into the exhaust for ^ said effect.
 
The line to the valve cover isn't gonna work it's best. That line needs vacuum to suck out any blow by.

I would ditch the breather filter and just run a vacuum line there and T it to your other vacuum line source that you already have for the block.

:werd: Although, I'd recommend keeping the PCV valve.

If your friend's car is sucking in oil, then the catch can isn't doing it's job.

Just install a filter when you go boosted, or install a slash-cut tube.
 
Can't you not put vacuum on both valve cover vent and crank case vent at the same time? Air needs in eh?

Rephrase. Your saying it is OK to put the same vacuum source on both vents?

I'm thinking now it might be better to have a closed catch can off of the crank case vent with vacuum from the intake manifold, and a closed catch can off of the valve cover vent with vacuum generated by the Bernoulli effect from either the intake charge when NA or the turbo's inducer charge when boosted.

Opinions?

Seems like basicly you all hate answering my questions... sorry I know I'm stubborn and a pain in the ass, but please help me anyway :) lol
 
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Yes, that would work fine. Installing a catchcan inline with the stock system in place means it'll work like stock but you keep it from sucking oil into the intake.
 
ok figured id just bump this back up instead of starting new..
so i just ordered a catch can and was wondering something..the black box on the back of the motr..has a hoes going into it and then another hose going from it to the pcv valve and then into the intake manifold. my question..should i just bypass the black box,,run the hose right from the back of the motor to the catch can,then from the catch can to the pcv valve,then back to the mani??
or do i even need the pcv valve???

also venting a valve cover..i have the general idea,,but i need o know what kind of fittings to use on the valve cover
 
no fittings for the valve cover required to my knowledge. to do it correct, you must remove the black stock box, seal the oil drainback hole on your block, then run a line from block vent barb to closed catch can, then line from closed catch can to intake manifold with a pcv check valve inline. the valve cover vent should go to a closed can from the valve cover vent barb, then another line goes from catch can to intake arm on an NA application. you can use 3/8s hose such as the high pressure pvc braided hose availabe at lowes, etc.

good injen?
 
sounds fairly easy but where is the return hole?and from what barb??the one coming from the block to the black box?
 
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