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Gaijin Smash Wayhoff

Crankcase Ventilation / Catch Can Setups

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Been doing a lot of research on proper set up for catch cans and have a few questions/ideas.

 

1. I notice some people go the extra mile and weld separate AN bungs to each valve cover instead of using the crossover tube. Any particular reason or just for looks?

 

2. Are the stock baffles in the valve covers good enough?

 

3. Most setups seem to run to atmosphere which I'm not fond of. Most other setups route to the intake pipe before the turbo as a source of vaccum. That's great but the thought of excess oil being dumped into my turbo and intercooler is not one I like. Does anybody know of a low power electric vacuum pump that could be used instead?

 

4. Anybody know of a good premade baffled catch can?

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Fuck catch cans,

I just blow everything out the exhaust.

I have 2 connections in my collectors for exhaust scavanged crankcase venting.

You can buy the kits at any hot-rod supply, and they include check valves to keep anything from plowing back.

Under heavy throttle, the exhaust will actually pull a vacuum on the engine.

On a turbo system, you put the connections into the down pipe.

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http://www.summitracing.com/parts/sum-120108

 

You end up with useless pig-iron V8 valve cover caps.

If you check around, you should be able to find the check valves by themselves.

The weld-in tubes are just pipe nipples (not to be confused with girl nipples), that you can find at any hardware store.

 

Here is where I put mine on my NA headers.

You should only need one in your down pipe.

post-3787-0-23380300-1363902821_thumb.jpg

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I run aluminum tubing up from the header about 8-12 inches (1/2" fuel line, and el-cheapo brass furrel fitting from lowes), then just normal 1/2" crank case vent hose to the cam covers.

Doing a single, I would use 3/4" hose & tubes, and a 1/2" pipe nipple.

 

And I think those check valves are available at any Napa, if I remember correctly they are from the old air injection days when detroit was pumping air into the exhaust manifolds.

The hot rod guys screw them directly onto the nipples welded on the exhaust, but I don't think they run as hot as a turbo.

I would mount them up at the end of the tubing.

 

I found some militaty surplus check valves that I use now, but they probably cost the US tax payer $500 each. You can bearly see them at the top of this picture.

post-3787-0-10488400-1363905788_thumb.jpg

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So when there's no vacuum are the gasses trapped or does the exhaust always create enough vacuum to open the check valves (i.e. at idle)?

 

 

Also, you have A/C???

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The check valves have very light springs, so there will never be any pressure build up in the engine.

You can even blow through them with your mouth, and unless you practice a lot giving blow-jobs, is less than 1 psi.

 

I have AC, but it's comming out before the new engine goes in this time around.

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I made a pretty boss setup for a supra awhile back using a moroso air/oil separator. Used four -10 male bungs, welded one over the hole on one side, filled the hole on the other, welded two of the -10s on that side and drilled through, returns to intake. Thing is baffled awesome. Have a very similar setup on my car. If your car is getting oil past that then you're having other problems.

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I like this one. http://www.jegs.com/i/Moroso/710/85604/10002/-1?CAWELAID=1710596333&catargetid=1784156173&&cagpspn=pla&gclid=CIzEzP6DkbYCFYbc4AodeUUAsg

 

I'm thinking with being turbo, it might be a good idea to run a catch can between the valve cover and exhaust.

 

Set up would be valve cover-> check valve -> catch can -> exhaust

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Why are you concerned with dumping an ounce or 2 of oil out the exhaust ?

These catch tanks are normally for people keeping their PVC systems legal, and so that no oil enters the intake.

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My main concern is burning oil. I don't know how much oil is making it out of the valve cover but I don't want to be rolling smoke while driving. I may start out without one and see what happens.

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How is the caged car coming?

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Caged car is waiting patiently in San Antonio. After Lonestar Rd 1 is over this weekend I should have room at the shop to bring it down and start cranking away. Parting out my parts JZX right now. What tubing is that cage made out of?

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1-3/4 DOM, per nasa rules.

 

In San Antonio ?

Crap, I sell it, it goes to Austin, then ends up back here.

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Don't get rid of any X8s without cutting the roof off, that car wouldn't look half bad if the ass hole who tried to weld in the sun-roof pannel hadn't did such a bull shit job of it.

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You shouldn't be dumping much oil out of any pcv system, if you are your outlets are too small and too much oil pooling in that area. If you have a small orifice it basically creates a venturi effect and will suck out nearby oil when crank case pressure goes a certain amount above atmospheric or the vacuum applied to the orifice. So you shouldn't need a catch can but some oil will always be drawn out of pcv. I also think the exhaust method is the best, probably the only way to have a vacuum on the crank case at high rpm with out a lot of complication.

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Great thread.

I have been looking into info on this recently on other forums, I was going to do 90 degree 1/2" NPT to -10 AN fittings on my valve covers, braided lines to a catch can of some sort... I am not wanting to recirculate the PCV's into my intake also.

But now I like Gordo's check valve setup better than a catch can... I'm just wondering if it will make a difference when I go to pass my car through Air Care... (a emissions test.)

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If you use brightly colored fittings & hoses, probably not.

But Earls, Russel, and others are now making black fittings that are a lot easier to pass any under hood inspections.

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engine bays don't really ever get inspected here, but my choice was going to be black fittings with black nylon braided lines anyway, not much of a heat score... I suppose the big single turbo would be though... lol

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It will probably make passing emissions testing more difficult. Definitely will increase Hc's in the exhaust, if its possible to negate the amount of increase I wouldn't know, no emissions testing here. Not sure how in depth bc's emission testing is either.

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the standards for my X7 are

Driving Mode HC Standard: 95 parts per million
Driving Mode CO Standard: 0.69 percent
Driving Mode NOx Standard: 1025 parts per million
Idle Mode HC Standard: 110 parts per million
Idle Mode CO Standard: 0.85 percent

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Yea doesn't mean much to me, only ever used a 4-gas analyzer once, not common equipment here. And with no emissions testing I'm not familiar with common ppm/%.

 

If you can/want to, try it and post the results, well if you can test it and fail without it getting pulled off the road. Maybe block off the exhaust pcv vent/re-route for the emissions testing if you cant check it. I am curious on the amount of increase it would have.

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