Most Effective Oil Catch Can
10-08-2007, 01:26 PM
#51
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^^^ wait....
No vacuum... engine off
High vacuum,TB closed, Engine idle
moderate vacuum... TB 1/2 open or so, driving conditions
Low vacuum... WOT, acellerating high load, squeeling tires, burning out, face smashed into the headrest, 3Gs of acelleration making you black out
These images are from HMAService.com...
RADU: even a boosted engine will have vacuum at the intake manifold. the Throttle body prevents the IM from being pressurized except durring WOT or 1/2 open. But regardless of that, if the stock breather is hooked up, it will be pressurized from behind.
No vacuum... engine off
High vacuum,TB closed, Engine idle
moderate vacuum... TB 1/2 open or so, driving conditions
Low vacuum... WOT, acellerating high load, squeeling tires, burning out, face smashed into the headrest, 3Gs of acelleration making you black out
These images are from HMAService.com...
RADU: even a boosted engine will have vacuum at the intake manifold. the Throttle body prevents the IM from being pressurized except durring WOT or 1/2 open. But regardless of that, if the stock breather is hooked up, it will be pressurized from behind.
10-08-2007, 01:39 PM
#52
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HHaha I actually tried that tanc, you are right, I'm sorry. The PCV valve does close if you try to blow through it (from the IM side).
My mouth needs to be washed with soap, but there's no need, I now taste oil from the PCV owned.gif
Sorry for all this, it just didn't make sense to me and all the stuff I read seemed to agree with my intuition.
DTN: yes, I was supposing the breather was just vented to the atmosphere, it's clear that if you run it from the intake pipes (before the TB) the crankcase will be pressurized with boost.
My mouth needs to be washed with soap, but there's no need, I now taste oil from the PCV owned.gif
Sorry for all this, it just didn't make sense to me and all the stuff I read seemed to agree with my intuition.
DTN: yes, I was supposing the breather was just vented to the atmosphere, it's clear that if you run it from the intake pipes (before the TB) the crankcase will be pressurized with boost.
10-08-2007, 01:58 PM
#53
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Well at least you guys can go buy a brand new PCV valve for $13........I went to get one from the shop here in the UK and the guy wanted £43 = $86.......WTF!!! If anyone feels like sending me one cheaper i'd gladley pay!!
10-08-2007, 02:05 PM
#54
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PCV = Positive Crankcase Ventilation.
It is a one way valve. End of story.
Bal, can't you just go to an auto parts store and get it cheaper? Don't go to a shop/garage/dealer for a part like this, this is a universal thing---like headlight bulbs or something, you can get it at any auto store.
Also, can someone explain why having a catch can hooked up between the PCV and the IM would be bad for a boost setup? What I am saying is to hook it up like stock, and have a catch can between them, so it would be in-line. Input from the can would be from the PCV, output from the can would be to the IM. Why would that not work? That's what I'm doing (N/A) and it is working wonderful, no spewing oil over the bay, catching a good amount of oil, and looks stock. No ricey chrome cans, I used an air/water separator and was able to hide it because its so small.
It is a one way valve. End of story.
Bal, can't you just go to an auto parts store and get it cheaper? Don't go to a shop/garage/dealer for a part like this, this is a universal thing---like headlight bulbs or something, you can get it at any auto store.
Also, can someone explain why having a catch can hooked up between the PCV and the IM would be bad for a boost setup? What I am saying is to hook it up like stock, and have a catch can between them, so it would be in-line. Input from the can would be from the PCV, output from the can would be to the IM. Why would that not work? That's what I'm doing (N/A) and it is working wonderful, no spewing oil over the bay, catching a good amount of oil, and looks stock. No ricey chrome cans, I used an air/water separator and was able to hide it because its so small.
10-08-2007, 02:28 PM
#55
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Actually, it also restricts the flow at idle so it's sort of two-way (as DTN mentioned), but I'll shut up smile.gif
The problem with going with the NA setup is that you also have to take care of the breather - you can't leave it in the intake as you will boost inside the crankcase, and at WOT there is no IM vacuum to suck the blow-by gas in, so the gas goes out through the breather (with a bit of oil).
The problem with going with the NA setup is that you also have to take care of the breather - you can't leave it in the intake as you will boost inside the crankcase, and at WOT there is no IM vacuum to suck the blow-by gas in, so the gas goes out through the breather (with a bit of oil).