crank case pressure question

Discuss topics related to the CA18DE and CA18DET series engines.
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ca18detgabby
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mmm240 wrote:because gabby had an idea. pfft
I suppose I should have started another thread and then been linked to this thread instead...........


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ca18detgabby wrote:
I suppose I should have started another thread and then been linked to this thread instead...........
Don't worry, all of the CA people have seen it anyways

Meaning from your post on. Unfortunately because there isn't much traffic here

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float_6969
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ca18detgabby wrote:
I suppose I should have started another thread and then been linked to this thread instead...........
NO! And thank you for not doing that! Searching FTW.

But in answer to your question, no that won't work.

the BEST way would actually be to have 2 catch cans, one for each side of the motor.

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under boost...PCV shuts, and only exhaust side vents, and galleries in rear of head allow pressure in intake rocker cover to vent via the exhaust cam cover..

So Niscort is right to say that both should be vented. Especially if you do get a lot of blowby, and run a high oil level.

My engine is rebuilt, and with the 'aussie way' of hooking up breathers, mine doesn't get a drop of oil in a catchcan hooked up to the exhaust side, and feed back to the pre-turbo intake piping.

ps.I temporarily didn't vent anything and piped everything to the PCV, which is fine on NA. But causes dipstick-missing related fires under boost...

Maybe you are just running too much oil,

OR

There is a breather hose that goes from bottom/back of intake cam cover, leading to the oil filter area. This pipe can get blocked with gritty carbon crap, and this can stop the breathers working properly under boost.

Getting to the pipe is not easy. And will involve a lot of swearing. Also note that the silicone hose connected to it is 1.25 inch, and hard to replace if cracked.

Chris

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float_6969
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You posted as I was revising my diagrams. This is close to how I'll be running mine once I get the CA in the S14.

niscort
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float_6969 wrote:IMHO, this is almost the best crankcase ventilation setup possible...
not for any car running a AFM.

catch can both sides FTW

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The_Chosen_One
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You live in FL go with the most illegal way, have the system routed to your exhaust BOYYAA.


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ri120
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a pcv valve system is basicly just used for emmisions. when the system is hooked up to the intake tube it is to burn the crankcase vapors instead of polluting the atmosphere. its sort of like a egr valve, but a little more primitive. a egr valve just fills up the combustion chamber with used air that just takes up space so we cal all run a leaner fuel/air mixture to keep hydrocarbons(unburnt gases) and co2(partially burn gases) down. this also helps with nox emmisions. so like a egr valve the vent system just burns up crud and lowers emmisions. ( and saving the enviorment at the same time. lol) a pcv valve is just a 1 way check valve letting vapors out and not letting anything in. when i get money to get my clutch and i finish the valve adjustments i will probly set a catch can up with all the with manifold blocked off, and the intake pipe blocked off so im not brning anything but fuel and air and the vent hoses runing into the can. i dont know if im going to try to run it sealed or vented

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Bwana
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The_Chosen_One wrote:You live in FL go with the most illegal way, have the system routed to your exhaust BOYYAA.
This is how I'm building mine. Very effective.

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float_6969
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I disagree. There are lots of corrsive gasses, acids, and plain old water (in the form of steam), that form as by-products of the combustion process that enter the crankcase via blowby. If you don't remove them somehow, they will slowly damage the internals of the motor.

On turbocharged motors this is especially noticeable as the extreme pressures experienced in the combustion chamber can actually pressurize the crankcase if the PCV system isn't hooked up properly. The problem with that is that as the gasses try to escape the crankcase, they can flow up through the oil drains for the head and prevent the oil from draining back into the oil pan, potentially starving the oil pump and causing bearing damage. It can also cause the dipstick to blow out. On most engines the dipstick is located near the exhaust manifold. This situation can pose a serious fire hazard.

At least run it vented. If you plug it off, don't be suprised if you start spraying oil all over the engine compartment via the dipstick.

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The_Chosen_One wrote:You live in FL go with the most illegal way, have the system routed to your exhaust BOYYAA.
That IS a good setup. I wonder how much those high temp check valves are? Any more info on it?

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ri120
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the only reasone i would run it sealed is to create a vaccum inside the crankcase. i kindof worded it wrong.not sealed sealed. i race sk mods also and i work on a team u can see a 15 to 20 horse increase by creating a vaccum or a neg pressure in the case

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That's true, but I thought you had to run thinner rings.

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The_Chosen_One
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float_6969 wrote:That IS a good setup. I wonder how much those high temp check valves are? Any more info on it?
The kit costs about $40 for the check valves. I bought all the stuff im just lazy to take off my downpipe. I'll do a baller write up again on it.

http://store.summitracing.com/...w=sku


bentvalves
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Its called a crankcase evacuation system, summit and such sell them.

When I had my PCV welded shut, and both intake/exhaust breathers going to a catch can, and the catch can routed to my midpipe.....I would smoke like a fool at idle.

I thought it was restrictor for turbo, so I got another smaller one.

Lack of PCV at idle ended up being the culprit, and once I sorted that, all was well.

Perhaps sending both the intake/exhaust to the same catch tank was the problem?


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float_6969
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Well after doing a bunch of research, that won't necessarily work well.

http://www.honda-tech.com/zerothread/1199935

last posthttp://www.turbobuick.com/foru....html

These systems are designed for NA setups where there are great variations in pressure in the exhaust pulse. Due to the gasses passing through the turbine, the pulses are evened out and the pressure changes aren't as great.

You'll still get some vac, but not as much as you would on a NA setup.

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float_6969
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The intake and exhaust cam covers are tied together near the front of the head infront of the spark plugs. They're all one body of air.

bentvalves
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In the end I have PCV going to intake as per stock, and exhaust breather going to a catch, with the check valve on the can, then leading to the exhaust.

Im thinking at WOT as revs climb, theres enough velocity in the 3" exhaust pipe to make effective bernoullis principle.

Have you ever held your hand near the end of your tail pipe when your car was on the dyno, or doing a burnout?

Greg

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float_6969 wrote:You'll still get some vac, but not as much as you would on a NA setup.
It also seems like positioning the ports farther downstream in the exhaust will eliminate the turbulence problems caused by the turbo. One guy I read of put his post cat and was pulling something like 5" of vacuum, which is FAR better than tapping the intake pipe will do (max of 1" vac as per honda-tech thread).

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float_6969
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That does make since, but now you've got a lot of tubing running around again. Seems over-complicated to me.

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The_Chosen_One
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float_6969 wrote:That does make since, but now you've got a lot of tubing running around again. Seems over-complicated to me.
When I do my install you'll see. Its really just 2 lines.

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I'm not argueing it's simplicity, but I'm saying that from what I'm finding, doing it just like they did on the Toyota, it may not work all that well.

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Supposedly the dude gain 60whp from doing it that way, but those guys are pushing over 800whp.

Overall mine is going right before the test/race cat goes. I added a O2 bung where the downpipe and floorboard meet so I have to have the check valves after it.

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I still haven't gotten around to setting up, but I have been wanting to get the oil catch / separator from a MazdaSpeed Miata since before I installed my motor. I even have a second oil return installed in my oil pan not in use yet... hook it up like you would an oil catch normally except it also has a drain back from the separator so the oil can drain into the pan, but the gaseous bits can get sucked out and burned off..

Problem was you couldn't actually order that part from Mazda easily and it was really expensive (like $150 or something) and there were no wrecked mazdaspeeds yet to steal one. And since, just kinda forgotten about it.. right now no room to place the thing anyways, need to make room. Once I relocate the battery maybe... my second drain back is on the front right of the oil pan.

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sjbsuperman1425
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ok, so its pretty obvious that 2 catch cans is the best possible situation. now if only using one catch can, would it be best to put it on the turbo side (setup #1) or put it on the intake side with the PCV valve?

bentvalves
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THE best solution, and I will only say this one time : )

is to find an sr20 partout, acquire the baffled breather box that sits behind the exhaust manifold used to keep oil down in the crankase, and plumb that b**** upsidown behind your intake manifold on the ca18. One mount lines up perfectly with a hole in manifold, the next bracket on the can needs extending about 1/2" or so. Modify the inlet/outlet of that tank as needed to plumb lines proper. Plumb it inbetween the line going from the oil filter housing to the intake valve cover there.

watch in awe as you no longer fill catch cans, and have the best breathing ca18det on the block!


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The_Chosen_One
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Or Or Or Or you can shut the hell up

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lol

order me some midnight purple paint with gold flake wouldya ?

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The_Chosen_One
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Already got that in stock.

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ks13, you are talking about that line on the back bottom part of the intake valve cover correct? and doesn't the KA have the same baffled breather box or no?


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