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-   -   Baffled by my Baffling (Valve Cover) (https://www.miataturbo.net/engine-performance-56/baffled-my-baffling-valve-cover-73945/)

thirdgen Jul 17, 2013 01:27 AM

Baffled by my Baffling (Valve Cover)
 
8 Attachment(s)
I am going to run a crank evac on Phase 1 of my new setup. The crank evac will be similar to this:
http://www.summitracing.com/parts/vpe-1189
and it will have a -10AN Male fitting to attach to. I want to run a -10AN brainded line to my valve cover breather which will be drilled out and threaded to accept a 3/8" NPT to -10AN adapter.
Debates: I most likely will not be running a check valve as I cannot find a check valve with a -10AN fitting on it.
Debate#2: Is the breather port acceptable to use for this? I.E., is the baffling sufficient?
The PCV side looks better as far as possibly having larger area to pull better vacuum, but the breather side looks "more restrictive" as far as keeping oil out of my exhaust.
Here's what the valve cover looks like with the baffle plates installed:
Attachment 82693
Here's what it looks like with them removed:
Attachment 82694
This is the breather side, note the tiny hole that transfers to the center of the valve cover:
Attachment 82691
This is the much larger, but more baffled area coming in from the PCV:
Attachment 82692

Braineack Jul 17, 2013 07:14 AM

and this is a thread, on the exact same subject:

https://www.miataturbo.net/engine-pe...-thread-46833/

FRT_Fun Jul 17, 2013 09:48 AM

gawd damn noobs

thirdgen Jul 17, 2013 09:59 AM

Crap.

Leafy Jul 17, 2013 10:04 AM

I'm sure you can find an industrial JIC check valve. Remember JIC and AN thread into each other and seal 99.9995% of the time.

thirdgen Jul 17, 2013 10:15 AM

True. Is a check valve really necessary though?? I just don't see how anything other than vacuum would happen due to the angle of the tube welded in the DP.

soviet Jul 17, 2013 10:43 AM

slashcuts suck

Leafy Jul 17, 2013 10:49 AM


Originally Posted by thirdgen (Post 1032968)
True. Is a check valve really necessary though?? I just don't see how anything other than vacuum would happen due to the angle of the tube welded in the DP.

If your back pressure is too high from a restrictive exhaust it can. And I've been reading about it on and off today, it seems on some cars they only make vac when in boost.

Also, if you keep the stock pcv valve and dont put a check valve in the exhaust slashcut you'll suck exhaust through the engine and into the intake manifold at idle and low load.

thirdgen Jul 17, 2013 12:44 PM


Originally Posted by Leafy (Post 1032984)
If your back pressure is too high from a restrictive exhaust it can. And I've been reading about it on and off today, it seems on some cars they only make vac when in boost.

Also, if you keep the stock pcv valve and dont put a check valve in the exhaust slashcut you'll suck exhaust through the engine and into the intake manifold at idle and low load.

My exhaust is 2 1/2" from turbine outlet to muffler, no cats, no resonator...just a muffler. I don't think it's restrictive...or is it?

I'm planning on plugging the PCV port and using the breather port to connect my crank evac to.


Originally Posted by soviet (Post 1032980)
slashcuts suck

Why do you say this?

soviet Jul 17, 2013 01:49 PM


Originally Posted by thirdgen (Post 1033053)
Why do you say this?

Glad you ask

https://i.chzbgr.com/maxW500/1021522688/h58BD3741/

Faeflora has a pair of slashcuts and from my experience they are awful. Main reasons being
- hoses running to your downpipe. downpipe removal becomes a massive, massive pain in the ass
- oily rear bumper due to all the crap burning
- can't really measure how well its working (with a catchcan you can check the contents)

Leafy Jul 17, 2013 01:55 PM


Originally Posted by soviet (Post 1033082)
Glad you ask

https://i.chzbgr.com/maxW500/1021522688/h58BD3741/

Faeflora has a pair of slashcuts and from my experience they are awful. Main reasons being
- hoses running to your downpipe. downpipe removal becomes a massive, massive pain in the ass
- oily rear bumper due to all the crap burning
- can't really measure how well its working (with a catchcan you can check the contents)

1. Use a good connection like an AN, and don't place it like an idiot.

2. Rear bumper shouldnt be oilly unless you have a blow by issue or a stupidly placed exhaust exit.

3. Sure you can, pull out your dip stick and put a rubber line over the tube and either run that to another map sensor you can log or a boost/vac gauge. If you're making vac in the crank case during boost, its working.

Or you could just put a catch can on the line if you felt like it.

soviet Jul 17, 2013 02:18 PM


Originally Posted by Leafy (Post 1033084)
Or you could just put a catch can on the line if you felt like it.

That actually might be the best idea ever. I could just use a slashcut as a vacuum source on my existing catchcan. That way it will, theoretically, also work while cruising.

thirdgen Jul 17, 2013 05:04 PM

I think FaeFlora used hose clamps and shit. I'm using AN fittings. No leaks for me.

rkim Jul 27, 2013 03:18 PM


Originally Posted by soviet (Post 1033092)
That actually might be the best idea ever. I could just use a slashcut as a vacuum source on my existing catchcan. That way it will, theoretically, also work while cruising.

Isn't this similar to bbundys setup as he described it in the catch can thread? Can drains to oil pan and slashcut with check valve pulls out air?

hustler Jul 27, 2013 06:04 PM

What's wrong with plugging the intake side and running a catch-can on the exhaust side?

GraemeD Jul 30, 2013 06:09 PM

It is not just about oil control, "MORE POWER" can be had
Moroso Vacuum Pump Test - Car Craft Magazine

I have been thinking about the best way to achieve this.

flounder Jul 30, 2013 07:13 PM

Anything :fael: has done to his poor miata, should not be forced upon any other miata. In fact, measures should be instilled to make sure the exact opposite happens.

Doppelgänger Aug 2, 2013 01:50 PM

Wait......some people are just learning that pulling vacuum on the crankcase will make more power? I thought this was common sense....with the exception of all the fucksticks out there with breather filters on their valvecovers or breather filters on a catch can. Those people are retarded.

concealer404 Aug 2, 2013 02:05 PM

1 Attachment(s)

Originally Posted by Doppelgänger (Post 1039543)
Wait......some people are just learning that pulling vacuum on the crankcase will make more power? I thought this was common sense....with the exception of all the fucksticks out there with breather filters on their valvecovers or breather filters on a catch can. Those people are retarded.


'Sup?

Currently topped with 3 Moroso breather filter. :giggle: <3


https://www.miataturbo.net/attachmen...ine=1375466750


https://lh4.googleusercontent.com/-P...906_134322.jpg

soviet Aug 2, 2013 02:13 PM


Originally Posted by Doppelgänger (Post 1039543)
Wait......some people are just learning that pulling vacuum on the crankcase will make more power? I thought this was common sense....with the exception of all the fucksticks out there with breather filters on their valvecovers or breather filters on a catch can. Those people are retarded.

I like the smell of blowby when I'm doing a pull.


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