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Open Breather Ventilation
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This method is adequate for ventilating crankcase gasses in turbocharged/supercharged cars because the extra blow-by will force its way through any filter quite easily. You want to make sure you provide as many sources as possible to allow the pressure to escape with ease.
For H, F, and D series engines you can use the stock PCV line(excluding the PCV valve), Breather Line, and tap an extra 1-2 ports in the valve cover if wanted. You can attach a filter directly to the line or connect them to 1or2 catchcans with a breather filter on top.
You want to place the catchcan in the highest possible location you can locate in your engine bay. This will allow the catchcan to collect blow-by gasses without consuming excessive oil and allow a drainback line to easily flow oil/gas mixture back into the engine(if you choose to use this feature).
The sole purpose of a catchcan in an open breather system is to "trap" oil and blow-by gasses so they do not contaminate your engine bay and the environment. The surface area in the lines and the catchcan facilitate this. Increasing the surface area by using steel wool or other means will certainly help capturing these gasses but will also restrict them from escaping. The best compromise is to use a baffled catchcan such as one Moroso manufactures.
On B series engines it is preferable to ventilate the crankcase gases through 2 ports located on the back of the block. This arrangement can be accomplished by removing the PCV chamber behind the Intake manifold bracket and sealing the stock Crankcase ventilation hole. If you are running the stock Intake manifold you will want to also plug the PCV port on the Intake Manifold as well.
The Crankcase ventilation hole can be sealed with one of these 3 methods:
1) Aluminum Freeze Plug (34.4mm-34.6mm)
2) Aluminum circular plate epoxied with Devcon Liquid Aluminum
http://www.devcon.com/devconfa...id=34
3)
http://www.z10eng.com/ makes a plug.
It is important that you seal this opening with an Aluminum plug and not a rubber one!
Remove the ports with a 14mm Allen(Snap-on) and install these 2 washers and ports as shown below(Honda part numbers shown):
Use reinforced high temp hose 5/8" ID. Their will be a port on the top of your block which normally connects a line to your PVC chamber. You can either seal this or T it off one of your ventilation lines. The last thing to do is place a small filter on your breather port located on your valve cover.
I ran this above setup for approximately 1 year with no problems. My car was daily driven hard boosting 17-18 psi. I tested this setup using the following configurations:
1) Drain-back feature to the one of the original lines
2) Back to the oil pan
3) Without the drainback feature.
When I removed the drainback feature I would fill the catchcan half full every 2-3 weeks. The evacuation lines would dis-color but never suck oil even when I used the stock Honda fittings without an anti-siphon tube. The contents of fluid collected inside the catchcan was mostly unburnt fuel and contaminants with very little oil. If you are experiencing excessive oil consumption in the catchcan I suggest you place your catchcan higher or do a leak-down test.
I suggest manually draining the catchcan instead of using the drainback feature to eliminate gasoline and contaminants from re-introducing themselves to your oil.
Bottom Line
Cost: 20-150 dollars(dependent upon open filter lines or use of catchcan)
Performance: Good(as long as their is enough ventilation)
Reliability: Good.
Environment: Horrible(no catchcan)- poor(Catchcan)