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-   Engine Performance (https://www.miataturbo.net/engine-performance-56/)
-   -   The deezums Catch Can (https://www.miataturbo.net/engine-performance-56/deezums-catch-can-85740/)

deezums Sep 1, 2015 10:57 PM


Originally Posted by good2go (Post 1262696)
But wait, just the fact that there is evidence of some leakage doesn't mean it's no good. He blew on that thing for some period of time, and the total space involved was virtually none, so my guess is that an entire crankcase volume would see next to nothing from a boost event lasting the time it takes to go through a few gears, no? :dunno:

I am in no rush to do anything with my valve, if that answers your question. It is much better than OEM, and isn't a bad or expensive thing while waiting for a check valve to ship. What little it leaks is probably just due to the tolerances on the plastic. If you are creative I bet it can be fixed.

Aiden drives a lot harder than I do, and breaks more things. :party:

good2go Sep 1, 2015 10:57 PM


Originally Posted by patsmx5 (Post 1262699)
Who knows? How much boost? Maybe it leaks worse when you apply 20 PSI instead of 0.2?

The easy simple proven way to fix this problem is install a check valve that's actually designed to see pressure levels that we turbo miata folks see.

Well, I'd expect that any self respecting MT member could must far greater than a measly 0.2, but who knows, maybe Aidan only excels at applying negative oral pressure instead.

18psi Sep 1, 2015 11:16 PM

leaving this here
https://www.miataturbo.net/diy-turbo...re-test-80353/

and ignoring the retarded check valve conversation

deezums Sep 1, 2015 11:17 PM

Hehe :giggle:

aidandj Sep 2, 2015 01:24 AM

<p>I would hope that I could apply more pressure than that.</p><p>Should I hook up my 2k psi of argon to it?</p><p>I was thinking about adding a nipple to my oil cap and running a dedicated map sensor for it so I could log on the megasquirt.</p><p>tommy im gonna have to side with pat on this one. check valve &gt; pcv.</p><p>I also realized that because this closes under boost it will work for my boring stock 1.6 all the way up to a big high boost build.</p><p>You just need to vent the other side properly.</p>

Der_Idiot Sep 2, 2015 02:54 AM

1 Attachment(s)
bbundy puts a crank vent in his car to help with blowby blowing oil trying to return in the drains back up and into the head, causing oil to pool and in turn causing it to get sucked out the PCV side port because the drain and air channel hole by the baffle is literally in the back corner, I mean really Mazda? Ya couldn't put a small baffle chamber in the middle and put the port up there? Would avoid half of all of this problem.

There's a raised drain hole in that back corner that's supposedly for crank pressure to return bypassing the oil return; it's offset a quarter inch in my head inboard, about 2" down, I'm guessing to make room for something else in the casting, but otherwise is 1/2" in diameter.

https://www.miataturbo.net/attachmen...ine=1441176892

Oh, Aidan. Next time you pull your VC just drill the hole connecting the middle baffle chamber to the exhaust side port. It's only a 1/4" hole that I drilled in small steps up to 29/64" which should be plenty large enough for what's needed to vent.

aidandj Sep 2, 2015 03:01 AM

Im not worried about the drilling. I just don't want to pull my valve cover.
<br />
<br />Next engine will probably have all those holes drilled out, and some fat hose on the exhaust side, maybe a slashcut to the downpipe.

aidandj Sep 2, 2015 03:43 AM

Also, Bob had issues with that. Big puffs of smoke.

deezums Sep 2, 2015 05:08 AM

You say you have a problem with puffs of smoke, yet you say slashcut? We all know those make smoke, right?

I also don't see how Bob's setup like above could puff smoke, doesn't look like he vents the can to the intake manifold at all. Are you sure he wasn't just filling the can?

Bob has no need of PCV, he is in boost more often than not. I can't imagine him using PCV.

aidandj Sep 2, 2015 08:50 AM

The slashcut was pulling oil up from the catch can. And I mean PUFFS of smoke
<br />
<br />
<br />
<br />Slash cut is to pit vacuum on the crankcase while under load.

Der_Idiot Sep 2, 2015 02:45 PM

He deleted the PCV hose and it resolved a lot of that issue if I recall correctly. The shitty baffles there make it real easy to suck out volumes of oil in short order especially on hard lefts.

patsmx5 Sep 2, 2015 02:58 PM


Originally Posted by deezums (Post 1262725)
You say you have a problem with puffs of smoke, yet you say slashcut? We all know those make smoke, right?

I also don't see how Bob's setup like above could puff smoke, doesn't look like he vents the can to the intake manifold at all. Are you sure he wasn't just filling the can?

Bob has no need of PCV, he is in boost more often than not. I can't imagine him using PCV.

Total guess on my part, but I would guess he had something connected to the intake manifold to allow it to smoke that much. That, or a slash cut in the exhaust, but my guess is on intake manifold.

aidandj Sep 2, 2015 04:13 PM

<p>Do you guys not read what I post. 2 posts ago I said that the slashcut was pulling oil from the can.</p>

psyber_0ptix Sep 2, 2015 04:28 PM

for some reason, I couldn't help but giggle when I saw the poof of oil

aidandj Sep 2, 2015 04:29 PM

<p>I thought it was awesome. I want that on mine.</p><p>SMOKE SCREEN!!!!</p>

Braineack Sep 4, 2015 11:26 AM


Originally Posted by aidandj (Post 1262565)
<p>Other side is open to a little filter.</p><p>Check valve = pcv.</p><p>Check valve $</p><p>PCV $$$</p>

a pcv CAN work as a check valve, however, the plunger doesn't always seal with pressure behind it. plus a pcv can allow airflow in either direction depending on the conditions.

a check valve is one way only.



also: do a leakdown test.

hi_im_sean Sep 7, 2015 12:07 PM


aidandj Sep 7, 2015 12:19 PM

Only good to 100psi, not worth it.

good2go Sep 7, 2015 12:20 PM

Wouldn't there be a pressure drop across that filter though, as in, it could cause measurable back pressure?

hi_im_sean Sep 7, 2015 04:06 PM


Originally Posted by good2go (Post 1263916)
Wouldn't there be a pressure drop across that filter though, as in, it could cause measurable back pressure?

If you look at the specs compared to the one Aidan and deezums are using, it flows almost 3 times as much, but only filters to 40 microns, vs 5.

I ordered 2 this morning, and 3 check valves, ill let you gheys know how it works.


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