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Old 10-22-2015, 01:54 PM   #41
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angle of insertion is key.
in cars and in humans.
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Old 10-22-2015, 01:54 PM   #42
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I haz :
Vibrant AN-10 Check valve
20+ feet of AN-10 hose
allthefittings.

Just don't have a vac gauge/catch can. Guess I could ghetto rig something with a pvc plug and hook it up to a spare VDO boost gauge, and assume a given loss for catch-can placement.

Sounds like a tomorrow problem.
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Old 10-22-2015, 01:57 PM   #43
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bro. just run the hose everywhere
tentacle raep crankcase ventilation

you can even run it through the drivers seat for those days when chipotle gives you blow-by
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Old 10-22-2015, 01:58 PM   #44
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Just make a crappy water gauge. It will have better resolution than a boost vac gauge.
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Old 10-22-2015, 02:08 PM   #45
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I've got two of the crankcase ventilation extractors in the exhaust system of my old 68 gto. I tested it once by putting the hose in a gallon jug of water and blipping the throttle. It drew all of the water out of the jug with just one blip. It may have taken 2 seconds. I just don't want one on my Miata. It will need to be plugged if you ever use a chassis dyno.
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Old 10-22-2015, 02:13 PM   #46
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Quote:
Originally Posted by sixshooter View Post
I've got two of the crankcase ventilation extractors in the exhaust system of my old 68 gto. I tested it once by putting the hose in a gallon jug of water and blipping the throttle. It drew all of the water out of the jug with just one blip. It may have taken 2 seconds. I just don't want one on my Miata. It will need to be plugged if you ever use a chassis dyno.
Yes, this is how well a properly setup slash cut works.

Also, pics of 68 GTO aren't working.
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Old 10-22-2015, 05:32 PM   #47
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Quote:
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The whole bong rip analogy had to have been made by someone ripping a bong. That's how bad it is
Right. because you still don't understand it.

Smoke represents blowby, the blowby doesn't completely evacuate till a source of fresh air other than blowby is added, like all stock PCV setups. If there is no fresh air whatever blowby manages to exit the system is immediately replaced with more blowby, nothing more.

If you never add fresh air, never pull the bowl, there is always blowby in the crank volume, pretty simple really, that's the extent of the analogy.

If you still have to argue the efficiency or necessity of fresh air source in PCV setup, I can't do anything for you. Bong rips included.
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Old 10-22-2015, 05:36 PM   #48
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I don't rip bongs, bro.
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Old 10-22-2015, 05:48 PM   #49
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Attached Thumbnails
Please not another crankcase ventilation thread.-80-billy_madison_insult_f42f7bfafb0a0fd1323c70d5a16749cecde32610.jpg  
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Old 10-22-2015, 05:50 PM   #50
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Stop looking at me swan!
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Old 10-22-2015, 06:55 PM   #51
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If you drill a hole in the top of the cam cover to introduce air, then you do a 300whp pull, blowby will come OUT of that hole.

Dann
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Old 10-22-2015, 07:00 PM   #52
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Yeah, and your point is?

At all other points of operation, with a PCV system, that outlet hole is an inlet hole. It is the same exact way on a stock miata valve cover, massive gaping hole through a half-asssed catch can. It goes to the intake past the MAF meter because all air goes in/out of there goes to the intake sooner or later, same as a recirc BOV.

The only reason air exits the hole on said 300hp run is because the PCV is closed, there is no vacuum in the crank. If it were a bitchin' big cube motor doing 300hp at 50kpa map, no blowby would exit said hole.

Come at me bro!
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Old 10-23-2015, 04:24 PM   #53
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You dont need a check valve, nothings flowing up that pipe (unless your neighbour decides to stuff a tennis ball up your rear end). Catchcan may or may not stop the bumper oil smell smokescreen hilarity. Not sure yet.

Quote:
Originally Posted by sixshooter View Post
It drew all of the water out of the jug with just one blip. It may have taken 2 seconds.
Wow. Nice. What hp? Exhaust/slashcut hose dia?

In 4 chipotle blowby flowrates

Deezums, open your oil cap at idle and tell me if the blowby comes in or out. Put a sliver of paper on top if you cant tell. You seem very strongly opinionated on this... have another toke.

Aside from the PITA of drilling another hole in my VC, why isnt this a good idea:



Im sick of these PCV threads too
Attached Thumbnails
Please not another crankcase ventilation thread.-80-pcv_5a93aaee53eab3e1ff72fef29e9383d9b5ac187a.png   Please not another crankcase ventilation thread.-80-pcv_8a1927e9aff4770229be5fd8a68ad6f790443c63.png  

Last edited by sparkybean; 10-23-2015 at 04:45 PM.
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Old 10-23-2015, 05:32 PM   #54
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Quote:
Originally Posted by sparkybean View Post
You dont need a check valve, nothings flowing up that pipe (unless your neighbour decides to stuff a tennis ball up your rear end).
Ever heard of a backfire? I would never run a pipe from my exhaust to crankcase without a check valve.
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Old 10-23-2015, 06:31 PM   #55
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Quote:
Originally Posted by sparkybean View Post
You dont need a check valve, nothings flowing up that pipe (unless your neighbour decides to stuff a tennis ball up your rear end). Catchcan may or may not stop the bumper oil smell smokescreen hilarity. Not sure yet.



Wow. Nice. What hp? Exhaust/slashcut hose dia?

In 4 chipotle blowby flowrates

Deezums, open your oil cap at idle and tell me if the blowby comes in or out. Put a sliver of paper on top if you cant tell. You seem very strongly opinionated on this... have another toke.

Aside from the PITA of drilling another hole in my VC, why isnt this a good idea:



Im sick of these PCV threads too
What the **** is this ****? Are you supposed to be telling me something I don't know?


My argument was that fresh air is required, you drew a fresh air line. I wish I could take a toke, it'd make dealing with you stupid turds easier.
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Old 10-23-2015, 07:38 PM   #56
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Maybe i misunderstood somewhere. Irreverent maybe, whatever, besides the point.

Tell me why that setup is bad. I can paint all day.
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Old 10-23-2015, 08:00 PM   #57
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0KPA is not a thing, the PCV is open and doing things anywhere south of 98.5kpa here.

So, without check valve and in a high overrun condition (hardly any exhaust flow) largest intake manifold vac you'll ever see (16kpa for me) you'll probably pull exhaust into the crank.

The main reason it fails is slashcut. If there is PCV there is no need for slashcut, if there is slashcut, there should be no need for PCV. Running slashcut on the street is ******* stupid, 99.9% of the time you have intake manifold vac, and the pcv works just fine.

Opening the oil cap at idle will be an inlet hole, no blowby will escape. Opening the oil cap is the same thing as running the exhaust side vent to the air cleaner which is all I've been arguing for. If you left the oil cap off and ran up to 20PSI, of course blowby will take the path of least resistance and spatter oil all over your hood.
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Old 10-24-2015, 01:43 PM   #58
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Run a check valve. Cheap and easy insurance. It has been shown here that there can be several lbs of pressure in even a straight pipe or with a straight through muffler.

Mine are on a 455 Pontiac engine with dual 2.5in exhausts and long tube headers. The extractors are in the headers' 3in collectors. It has Flowmasters, for reference.
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Old 10-24-2015, 02:53 PM   #59
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Summit Racing has crankcase evacuation kits with check valves for $39 that is enough to do 2 cars. Two of you guys should share one.
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Old 10-24-2015, 03:12 PM   #60
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Sixshooter, seeing as youre running a slashcut, and by the sounds of it consider it to be working well, what would you say its biggest downsides are?

Do you end up with a lot of oil on your bumper? Clouds of smoke/smells? Ta.
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