Exhaust Scavenge & PCV Delete
#21
By plugging the PVC port how can air flow through the crank case?
(Please correct me where I may be wrong but) I think the crank case is designed to have air flowing through it to vent out gasses and blow by. The stock design is that the line between the intake mani and the valve cover provides vacuum so that air is pulled through the line that is attached to the intake pipe. Thus air flow from the intake pipe, through the crankcase and out into the manifold. A catch can on the PCV line prevents the oil caught in this flow from making it into the manifold (and one on the vent line prevents it from dripping into the intake pipe during high throttle).
If anything I would have suspected that you should actually connect your red line to where the PCV valve was, stick a filter on the crankcase vent (where you have the red line going now), and keep the green line where is.
Again please correct me where I may be wrong, I am simply interested in learning more about this
(Please correct me where I may be wrong but) I think the crank case is designed to have air flowing through it to vent out gasses and blow by. The stock design is that the line between the intake mani and the valve cover provides vacuum so that air is pulled through the line that is attached to the intake pipe. Thus air flow from the intake pipe, through the crankcase and out into the manifold. A catch can on the PCV line prevents the oil caught in this flow from making it into the manifold (and one on the vent line prevents it from dripping into the intake pipe during high throttle).
If anything I would have suspected that you should actually connect your red line to where the PCV valve was, stick a filter on the crankcase vent (where you have the red line going now), and keep the green line where is.
Again please correct me where I may be wrong, I am simply interested in learning more about this
#22
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By plugging the PVC port how can air flow through the crank case?
(Please correct me where I may be wrong but) I think the crank case is designed to have air flowing through it to vent out gasses and blow by. The stock design is that the line between the intake mani and the valve cover provides vacuum so that air is pulled through the line that is attached to the intake pipe. Thus air flow from the intake pipe, through the crankcase and out into the manifold. A catch can on the PCV line prevents the oil caught in this flow from making it into the manifold (and one on the vent line prevents it from dripping into the intake pipe during high throttle).
If anything I would have suspected that you should actually connect your red line to where the PCV valve was, stick a filter on the crankcase vent (where you have the red line going now), and keep the green line where is.
Again please correct me where I may be wrong, I am simply interested in learning more about this
(Please correct me where I may be wrong but) I think the crank case is designed to have air flowing through it to vent out gasses and blow by. The stock design is that the line between the intake mani and the valve cover provides vacuum so that air is pulled through the line that is attached to the intake pipe. Thus air flow from the intake pipe, through the crankcase and out into the manifold. A catch can on the PCV line prevents the oil caught in this flow from making it into the manifold (and one on the vent line prevents it from dripping into the intake pipe during high throttle).
If anything I would have suspected that you should actually connect your red line to where the PCV valve was, stick a filter on the crankcase vent (where you have the red line going now), and keep the green line where is.
Again please correct me where I may be wrong, I am simply interested in learning more about this
I could have put the red line on the PCV but I still would not want the filter on the crankcase I would have plugged the other crankcase connection instead.
I choose to delete the PCV and use the other valve cover connectiong for 2 reasons:
1. Closer to the location where I am mounting my catch can and closer to the exhuast.
2. I drilled out the hole to a large size so that I could get a large vacuum source.
Hope this makes sense
#23
I'm just a little confused because the point of crank case ventilation is to remove unburnt fuel and exhaust gas that escapes the piston rings into the crank case. Why would Toyota use a flow of air to remove these contaminants if a vacuum is more effective? Simply plugging the crank case vent port on the valve cover while leaving the other port connected to the vacuum manifold would create the same vacuum effect within the crank case so why wouldn't they choose this over the design they did use?
#24
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I'm just a little confused because the point of crank case ventilation is to remove unburnt fuel and exhaust gas that escapes the piston rings into the crank case. Why would Toyota use a flow of air to remove these contaminants if a vacuum is more effective? Simply plugging the crank case vent port on the valve cover while leaving the other port connected to the vacuum manifold would create the same vacuum effect within the crank case so why wouldn't they choose this over the design they did use?
#25
Alright I think I understand the advantages of bypassing the reticulation into the intake path.
But I'm still a little fuzzy on why you wouldn't want to leave the other port unplugged creating an air flow through the CC. I feel like the way it's set up now just puts the CC under vacuum which would pull out any blow by in gas form, but any liquid blow by would just sit there wouldn't it?
A flow of air through the crankcase would diffuse gaseous blow by out and also catch any liquid
But I'm still a little fuzzy on why you wouldn't want to leave the other port unplugged creating an air flow through the CC. I feel like the way it's set up now just puts the CC under vacuum which would pull out any blow by in gas form, but any liquid blow by would just sit there wouldn't it?
A flow of air through the crankcase would diffuse gaseous blow by out and also catch any liquid
#26
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Alright I think I understand the advantages of bypassing the reticulation into the intake path.
But I'm still a little fuzzy on why you wouldn't want to leave the other port unplugged creating an air flow through the CC. I feel like the way it's set up now just puts the CC under vacuum which would pull out any blow by in gas form, but any liquid blow by would just sit there wouldn't it?
A flow of air through the crankcase would diffuse gaseous blow by out and also catch any liquid
But I'm still a little fuzzy on why you wouldn't want to leave the other port unplugged creating an air flow through the CC. I feel like the way it's set up now just puts the CC under vacuum which would pull out any blow by in gas form, but any liquid blow by would just sit there wouldn't it?
A flow of air through the crankcase would diffuse gaseous blow by out and also catch any liquid
#27
Iv always been under the impression that the position of the port on the exhaust being at a 45 degree angle going with the flow of the exhaust would pull a slight vac much how an airbrush works. again this is just the impression I get. Id have to look it up though since this is something i havnt done.
#28
#29
Lol sorry bout this confusion.
It's just lookin to me like the port on the exhaust creates a vacuum in order to pull blow by out of the crank case. Filtering the other end would allow air to be pulled by this vacuum through the crank case and out the exhaust catching blow by as it goes.
Think about a drop of water inside of a straw. Suck one end of the straw with the other end open. Air will move through the straw and bring the droplet with it. Now if you plugged the other end rather thank leaving it open, the whole straw goes under vacuum and the droplet won't move at all.
It's just lookin to me like the port on the exhaust creates a vacuum in order to pull blow by out of the crank case. Filtering the other end would allow air to be pulled by this vacuum through the crank case and out the exhaust catching blow by as it goes.
Think about a drop of water inside of a straw. Suck one end of the straw with the other end open. Air will move through the straw and bring the droplet with it. Now if you plugged the other end rather thank leaving it open, the whole straw goes under vacuum and the droplet won't move at all.
#31
I beleave this is all based off of Bernoulli's principle like as stated in the link i posted earlier.
http://www.scienceclarified.com/ever...lications.html
http://www.scienceclarified.com/ever...lications.html
#32
#34
Yeah I know its an old thread but I figured I'd try reviving it since there seems to be some pretty knowledgeable people in here. I plan on doing this to my tC in the near future but I'm running an open dump which could pose as a major problem since the majority of the gasses would be routed out of the dump at full boost when the rpm's are highest. Hopefully you guys will still be following this and throw in some opinions. Also how did this work for the guy who did it?
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