CrankCase Evacuation System

[djuosnteisn]

The side effects of a VTA valve cover ONLY exist if the stock pcv system is kept, dumping CC vapors into the intake manifold.

If you go with a venturi in the exhaust, then non of that vapor will reach your intake, and you shouldn't have any LTFT issues like deadman. This would cure your trims too deadman!

[SilverDemon]

I think I have the solution in using a dual vacuum set up, the intake mani for the idle and low load situations, and the exhaust for the "in boost" situations. I have my catch can out of the car and just finished modding to accept the exhaust venturi and a vac gauge. I will be reinstalling it tomorrow and doing some testing, so with fingers crossed this should be it for the crank case evacuation building.

[spnkr21]

will u need 2 catch cans if you do this?

[SilverDemon]

No, if everything works out, one catch can will do.

[spnkr21]

Are you just going to put a T on the "OUT" of the CC, where one goes to the venturi and the other goes to the intake mani?

[SilverDemon]

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[Speedie6]

Originally Posted by spnkr21 will u need 2 catch cans if you do this?

The check valve on the exhaust, and the second PCV on the IM which will act as as check-valve will make it so that whichever has the higher vacuum will be open while the other will be closed.

[SilverDemon]

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[Speedie6]

Hmm. That is interesting!

[spnkr21]

So what if you had 2 catch cans. Would that help get just vaccuum at wot with the venturi and then vaccuum with IM during cruising. That way they're not fighting eachother. What vac did u get when u had just the venturi hooked up under wot?

[Speedie6]

Originally Posted by SilverDemon This leads me to wonder if an actual check valve in place of the Napa PCV would prove to be more of a safety measure.

So, you are saying pressure is coming through the PCV you added to the IM? In that case, yeah, sounds like you need an actual check-valve. Maybe another Moroso. Or, is there a check-valve design that would more directly plug in there? I looked at check-valves at Jegs, and they have a lot of expensive ones designed for fuel. Didn't quite find one exactly appropriate for our needs. I'm sure they exist, just, didn't find it.

Originally Posted by spnkr21 So what if you had 2 catch cans. Would that help get just vaccuum at wot with the venturi and then vaccuum with IM during cruising. That way they're not fighting eachother.

Wouldn't buy you anything. They still have to T into the PCV. Sounds like he just needs a real check-valve.

[SilverDemon]

I have thought about this after the testing results, I wonder if the pressure is just from the Napa pcv not acting fast enough, there is a spring inside the valve that is designed for metering air. I thought about another Moroso check valve, but I would like to try some other options and maybe some bench testing to see how fast some of the different check valves react.

[MATT DAMOND]

Silver, why not put another check valve between the mani and the CC? That way the valve closes under boost, and is open when vacuum in the mani is present.

I'm sure that a regular Mazda PCV valve would do the trick.

[Speedie6]

Originally Posted by MATT DAMOND Silver, why not put another check valve between the mani and the CC? That way the valve closes under boost, and is open when vacuum in the mani is present. I'm sure that a regular Mazda PCV valve would do the trick.

He did exactly that already, except he used a Napa PCV valve which was a part recommended by Cobb in their whitepaper on their recommended catch-can configuration. And it looks like at least the Napa part is not acting like a real check-valve. My understanding is that PCV valves are not really check-valves, they have a metering capability. So, I think he needs a real check-valve.

[JumpingJackson]

Silver Demon, What catch can are you using that has 2 outlets and 1 inlet? (looking at that diagram)

[Speedie6]

Originally Posted by JumpingJackson Silver Demon, What catch can are you using that has 2 outlets and 1 inlet? (looking at that diagram)

The SilverDemon special, of course! He said he made it himself.

[SilverDemon]

Thanks Speedie, I am using the one I made. I had modified my original version to accept the second vacuum source from the venturi pipe. The original version worked great, it would catch about a cup or so of sludge every oil change (2500 - 3000 miles)

I just ordered another Moroso check valve from Jegs, we will see what happens.....

[Speedie6]

Originally Posted by SilverDemon The original version worked great, it would catch about a cup or so of sludge every oil change (2500 - 3000 miles)

The original version worked great, so, you had to go fuckin' with it!

Seriously, I like the work you doing, man. I bet the Moroso check-valve, unless you get a fucked one like me, will work great. I haven't contacted Jegs yet about mine.

[SilverDemon]

Thanks.....I often wonder sometimes why we work on things that were fine to begin with.......LOL!

[Speedie6]

Originally Posted by SilverDemon Thanks.....I often wonder sometimes why we work on things that were fine to begin with.......LOL!

Jegs and Summit Racing sell several brands of basically the same thing. Like there is a Jegs brand that you can get their brand check-valve for about $4 cheaper than the Moroso brand. It could be just the Moroso part just with the Jegs name on it. But it might not, as their weld-in tube is not the Moroso part, you can tell from the picture.

None of the other brands I found sold the check-valve as a separate item. Not that it matters much, I just thought it might be of interest to compare the quality of different brand check-valves. But, maybe not.

[SilverDemon]

I looked at work today, but could not find anything that had a light enough spring to work the way we want it to. Most of the ones were 25 psi or greater......

[Speedie6]

Originally Posted by SilverDemon I looked at work today, but could not find anything that had a light enough spring to work the way we want it to. Most of the ones were 25 psi or greater......

What kind of parts were you looking at? PCV values in order to try to get them to work as check-valves? If that is the case, then, I'd say we don't want a PCV valve at all.

[SilverDemon]

No, I am sorry I did not type what I was thinking.....I was looking into actual check valves from an industrial stand point, like pneumatic controls. But the ones I found did not work in the range we need.

[Speedie6]

Originally Posted by SilverDemon No, I am sorry I did not type what I was thinking.....I was looking into actual check valves from an industrial stand point, like pneumatic controls. But the ones I found did not work in the range we need.

Ah. I was thinking, 25 PSI, WTF? Didn' t make any sense.

I'm sure there are checkvalves perfect for our application. I just don't know where to look. But, the Moroso part will probably do fine.

[phantom3]

If you want as much vacuum in the CC as possible then I would go with a low cracking pressure check valve form a pneumatic supply store.
You cab get them rebuildable with metal housings. They come as low as 0.005 PSI cracking pressure. You would have to mount it vertically on the chassis some where. The nice thing is that there is no spring inside (hence the need to mount it vertically).
http://www.directindustry.com/prod/a...30-30194.html#

Too bad we couldn't figure out a way to use a vacuum generator.
http://img.directindustry.com/images...ctor-30200.jpg
Compressed air is run through the middle and the outside 2 ports (!!) provide the vacuum.

On a side note; You can also get orifice flow restricters in various diameters. They would make switching out pills really easy.

[SilverDemon]

Originally Posted by phantom3 If you want as much vacuum in the CC as possible then I would go with a low cracking pressure check valve form a pneumatic supply store. You cab get them rebuildable with metal housings. They come as low as 0.005 PSI cracking pressure. You would have to mount it vertically on the chassis some where. The nice thing is that there is no spring inside (hence the need to mount it vertically). Pneumatic check valves - - AIR-LOGIC - Valve, Clapper, Bursting disc

That was what I was looking for, I almost put in an order until I saw the operating temperature, 40* - 120*

[_Toxic_]

Good work! great pictures!

[phantom3]

Originally Posted by SilverDemon That was what I was looking for, I almost put in an order until I saw the operating temperature, 40* - 120*

Those are just examples. Those are all plastic units. They were the first pics I could find.

[SilverDemon]

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[Speedie6]

Originally Posted by SilverDemon I took the car into boost, the gauge went to zero, and then barley pulled off the zero mark. My gauge is not sensitive enough to accurately read low vacuum like this. I am going to guess at around .1 - .5 inches of vacuum, and at one time I saw a little pressure, but I am not going to take that too serious because I was in between shifts and it could have been a little needle bounce. All in all I am satisfied with the results. 1) I was able to achieve a slight vacuum in the catch can while under boost. 2) I now know for sure that there is no pressure in the catch can, and crank case. 3) The catch can is virtually "catching" everything all the time.

All this is great info, except, I thought with your original setup with just the venturi and no IM connection, you were getting more vacuum at boost. Not a lot, but, more than what you were seeing this time. Right?

[SilverDemon]

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[Speedie6]

Originally Posted by SilverDemon You are right.....I can't explain the difference in the readings. I will say that I like this set up better.......vacuum at low load and rpm, and a slight vacuum at boost conditions.

Great! Where did you get that idea from, he must be a fucking genius!

Seriously, 99.9% of the props go to you. You da man!

MATT DAMON has been participating in this thread, and he's the guy I was going to buy the cc kit from. He makes a kit using the Saikou Michi can. So, now that he has seen your results and what I am going to do, hopefully he can get me the kit soon.

[MATT DAMOND]

Silver, are you using a check valve between the OCC and the exhaust? I'm just wondering if that while the I/M is at high vacuum, can that vacuum over-power the venturi effect at the exhaust, and pull in exhaust vapors into the manifold? There might just be something I'm not seeing here.

Can you run VTA on the valve cover with this set-up?

Regardless, amazing work!

Speedie, I'll email you when I get the parts in, I'm still waiting on a shipment, but I expect it to be here either today or tomorrow.

[SilverDemon]

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[Speedie6]

Originally Posted by MATT DAMOND Speedie, I'll email you when I get the parts in, I'm still waiting on a shipment, but I expect it to be here either today or tomorrow.

Great. If your kit includes the secondary PCV, I won't need it, I'm going to buy another Moroso like Silver did.

Originally Posted by MATT DAMOND Can you run VTA on the valve cover with this set-up?

It sounds like there is still some debate on what is best to do with the valve cover. Some options include leave it stock, VTA, conceivably to another exhaust venturi. I think I heard that someone also put a cc on the valve cover but left it connected to the intake. Maybe that was DJ, not sure. Of possible note, the install instructions for the crankcase evacuation system show you connecting it to the valve cover, so, that seems to be the "standard" way to do it, with a NA V8 anyway.

There was also some people that modded the valve cover, and at one time, PTP had plans on modding the valve cover.

I suppose we could install a second venturi and hook it to the valve cover. Maybe that can be SD's next project, figure out what best to do there.

Yeah, we'll get SilverDemon to do it! He likes projects!

[superskaterxes]

i have my valve cover tapped for my occ and i put a plate in to block off the stock PCV box.

btw the other stock port to the CAI is still stock.

[SilverDemon]

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[Speedie6]

Thanks for all your hard work on this, SD. As far as parts, the Moroso check-valve has a 1/2" NPT fitting, correct? So, I guess you got a 1/2" NPT to 5/8" hose barb adapter?

Since I'm getting the Saikou Michi kit from Matt, I'll need to get a T. I'm sure I can find a 5/8" hose T.

I've got my second Moroso check-valve on the way from Jegs.

Originally Posted by SilverDemon in my opinion it would be best to either keep it to the inlet pipe, or vent to atmosphere. I really don't see an advantage to either.

Well, I think some people said there was some crap coming through the valve cover connection. I think I remember even hearing of one person that put a second CC on that connection, but, I could be mistaken. At any rate, it is my expectation that I should be eliminating sufficient crap that I can leave the valve cover stock.

[SilverDemon]

Yes, you are right, I used a 1/2" NPT to 5/8" barbed adapter. Yeah a "T" will have to put in the hose, those can be found at most home improvment stores.

[Speedie6]

Originally Posted by SilverDemon Yes, you are right, I used a 1/2" NPT to 5/8" barbed adapter. Yeah a "T" will have to put in the hose, those can be found at most home improvment stores.

I don't think a 5/8" hose barb T is a particularly common size that you would find at Home Depot. As I said, I found it online in brass for about $16. In nylon, it was about about $1.50. The temp where it is at is probably okay to go nylon.