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Discussion Starter #1
ok so i want to do a proper venting set up on my motor for the summer. i am going to weld in 2 -10an fittings in the valve cover to a vented catch can. i was just wondering where on the back of the block do u hook up the drain back line from the catch can? i would prefer to have it drain back to the block rather then dumping on the ground and it is easier then emptying the catch can all the time. i am looking for around 350+ next summer for my set up so i think the venting is a must. anyone with this set up have any input? i have been told some people tap the black box on the back but i also heard that there is a plug somewhere in the back of the block that u could use aswell. thanks. go autoworks has a set up similiar to what i am looking for on his new build.
 

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El Noob
98 Civic EX/ 86 MR2
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You know, I was always interesting in Knowing the Purpose of them 2 hoses coming out of the Valve Cover. I use to see a few Engines like that at shows.

Good Luck. Please allow me to sit back and Learn also:popcorn:
X2.
 

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Discussion Starter #4
it to allow the extra pressure that builds up in the block to get out faster. to eliminate blow by in the block. but when u do this oily air vapour is carried through the lines into the catch can. u either have to dump the crap on the ground, take out the catch can and empty it, or hook up a return drain line that goes back into the block. i am just looking to see what others that run this set up are doing.
 

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Their is a good write up on honda tec about this, if you do your research you will find that a vent system is crap compared to other systems, many people use them, but regardless of what they say you need some kind of vacume on the block to releave pressure. unless i am misunderstanding your idea you will still have a ton of pressure build up under the pistons which will cause blow by and shorten the life of your motor and cause it to smoke like a bitch. Use google and search "Honda PCV System" and you should find the honda tec write up explaining the testing and results of several systems....good luck
 

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uhhohhhhhhhhh

He sad HT



JK man!
 

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Personally, I would not drain it back into the block. I'd keep an eye on how much mist/liquid is accumulating and make sure it's emptied when needed.

I don't know why you would dump it on the ground. I'm sure you can find an old bottle or something.
 

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97 honda coupe
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Put a one way valve where the PCV valve goes, then route your two AN fittings from the valve cover, to the catch can, and have it drain down where the PCV valve drains into, this way you have no fluid lost, and you dont have boost being shot into the crankcase.

(if this is wrong, ill look it up its been awhile since ive looked this up im just running mine vented, since my engine doesnt see high rpms usually.)
 

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www.rifftrax.com
1996 Civic Ex Sedan
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i've done a lot of reading about this and imo the optimal setup without using a vacuum pump is to have two fittings in the vc, the b&r 12an fitting in place of the black box on the back of the block, and a pitcock (like on the bottom of a large air compressor) at the bottom of the catch can to drain it easily. for a vacuum source, you will need to T into the pre-turbo intake which will provide a constant source of vacuum regardless of boost pressure.

here's the fitting i'm talking about from b&r:



it comes with a flange that bolts to the block so it is secured.
you can find b&r fittings on h-t or e-mail [email protected]
 

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97 civic
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I have read alot about this as well and a friend of mine is doing a vitara build going for 300whp+ how necessary is the venting via catch can instead of the stock pcv setup for a power level of about that. I know it reduces blowbuy and sludge but how many people are running or need this setup?
 

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this has to be one of the most talked about subjects ever! here is a link for one thread i often refer people to, since it leads to other topics and threads:

http://d-series.org/forums/showthread.php?t=78178

i agree with ddd4114, draining it back is a bad idea. the fluid is a mix of gas, carbon deposit, and oil. adding that back to your oiling system just means your filter is going to have to get it out of the oil or try to get it out of the oil. this doesn't include the fact that it thins out the oil itself. anywho...

also, like jew said, your going to need something for a vac during times of WOT. you should be applying -5 InHg at all times to correctly evac the crankcase, or so seems to be the consensus.
 

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Classic Man
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i would leave the stock black box, its basicly a free catch can

drill a hole into it and put a fitting in or weld a pipe to it, and use that as the drain back. this is what i do.

theres a pic of it on page 1 of my thread vv
 

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There's no need to remove the PCV valve and put a check valve in it's place because the PCV valve is a check valve. It's just part of the PCV system, which is why folks call it a PCV valve.

I did my setup like that (in Luke's thread) and ran it for about a year and it was fine, but a little too complex for what it does.

What I would do is just run a hose from the PCV valve and point it at the ground. Any blowby the engine needs to get rid will just blow out the hose to the ground while you're under boost, and you'll never see it, because it will be on the road 500-feet behind you.

As far as the hoses off the VC go, yeah, run two off the VC into the catchcan, and then run one hose off the catchcan into your IM or charge piping with a check valve to prevent the pressure going back into the head. That way the head gets it's gases sucked out during vac driving and into the catchcan, and they get dumped to atmo when you're under boost. You don't have to hack into the exhaust this way nor do run the risk of pressurizing the head under boost.

Here's the same setup the Luke talks about in that thread. I just made a different diagram for it.

 

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www.rifftrax.com
1996 Civic Ex Sedan
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What I would do is just run a hose from the PCV valve and point it at the ground. Any blowby the engine needs to get rid will just blow out the hose to the ground while you're under boost, and you'll never see it, because it will be on the road 500-feet behind you.[/IMG]
that may be fine for like 5psi or less, but if you're running anything more i would not recommend this. the pcv valve itself and the line on it are WAY too small to accommodate the crankcase pressure in a mid- to high-boost system. its like the difference between drinking with a regular straw versus a coffee stirrer.

think about it like this: honda setup the pcv system to deal with blow-by by using a constant vacuum source for the engine when it is naturally aspirated. so why even consider running a pcv setup with no vacuum under boost considering the increased blow-by that boost creates?

i know, i know....they couldn't vent it to the atmosphere for emissions reasons, but there is NO WAY that atmospheric venting is sufficient for turbo applications.
 

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if your wanting to run the car at the track, which im sure you do, if they see a hose running off the black box towards the ground, they will throw you out in a heart beat. why the hell would you wanna put that nasty looking blow-by gasses/ oil/condensation, onto the track where people are running the cars, thats a safety hazard, and shouldnt even be though about doing it that way...

its not hard to empty a catchcan.... and running the drain back into the black box is a stupid idea also. the key is to get the blow-by sludge, which is why you elliminating the stock pcv system in the first place, oh and also to get rid of the pressure build-up. get that fitting that jew was talking about, put it in place of the black box, run it to the catch can, run 2 off the valve cover to the catchcan, put these all about 3/4 way up on the catch can. then run a vacume line to it, but above all the other lines on the catch can.. and depending on the size of the catch can, just dump it every oil change. about 1hr worth of work
 

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Hi hater!
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Mine is rather simple but has seemed to work for a year now no issues with moderate amounts of boost 13-18psi. I gutted my stock pcv valve. I have a line from that to the catch can and then the other line to the breather port on the IM mani. Though I will be saying that I will be changing it soon to the big bungs welded into the VC. There are so many ways of doing this and they all seem to work.
 
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