Eliminated my breather tube heater
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Originally Posted by civicandtegra
i sense a fight
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send video of winner
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Originally Posted by hondatech
Air is not "pulled" into the valve cover from the intake tube. You are confused I think.
Yes, it is. The other end of the PCV system is on the underside of your intake manifold.
The intake manifold always has lower pressure than the intake arm (more vaccum) and thus when the PCV valve is open, air will move from intake, into crank case, then up into your IM.
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Originally Posted by Qbacca
Yes, it is. The other end of the PCV system is on the underside of your intake manifold.
The intake manifold always has lower pressure than the intake arm (more vaccum) and thus when the PCV valve is open, air will move from intake, into crank case, then up into your IM.
The intake manifold always has lower pressure than the intake arm (more vaccum) and thus when the PCV valve is open, air will move from intake, into crank case, then up into your IM.
So when under full boost, the PCV valve is closed, right? That isn't so good.
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The manifold always has lower pressure than the intake. But if there's a lot of blowby at WOT, that overwhelms the flow thru the PCV valve. In that case the flow direction reverses in that breather tube.
With a turbo it depends on where the breather tube is connected. One way is to connect the breather upstream of the compressor. That way you prevent pressurizing the crankcase. Under boost the PCV valve closes & whatever blow-by you have, flows into the intake. Yes it gets some oily mess into there, but at least it doesn't blow seals out of the crankcase.
With a turbo it depends on where the breather tube is connected. One way is to connect the breather upstream of the compressor. That way you prevent pressurizing the crankcase. Under boost the PCV valve closes & whatever blow-by you have, flows into the intake. Yes it gets some oily mess into there, but at least it doesn't blow seals out of the crankcase.
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From: Colorado
Many of you are confused.
The stock PCV system exists to take pressure and vapors out of the crankcase (both above and below the pistons) and suck it back into the intake manifold. The purpose is so that instead of venting it into the atmoshpere, you are sucking it into the motor with the air from your intake and combusting it (i.e., you burn it off and filter the exhaust with your cat instead of just venting it out into the air).
Stock, its setup for optimum emissions and worst performance. There are 2 general situations this stock PCV sytem can be in: Idle/crusing (vacuum system), and WOT (atmospheric pressurize/perhaps boost).
1) Like someone said previously, the intake manifold has a lower pressure. When you're idling, the vacuum in the IM is higher than that anywhere else in the system, so it draws the oil vapors from the crankcase (both the back of the block and the valve cover) into the intake manifold for combustion. You are sucking up nasty oil vapors and burning them (which premotes detonation). The only upside to having the stock pcv lines hooked into the IM and intake is that the vacuum they provide in the crankcase can actually "pull on" the rings to create a better ring seal. This only improves the ring seal while under vacuum conditions (it doesn't increase your compression or help your rings seal better when you're racing).
2) at WOT, the crankcase becomes pressurized. The valve cover vent and stock separation box (the black box on the back of the block) allow extra pressure from the crankcase to vent into the intake/intake manifold. This extra pressure pushes out the oil vapors into your intake air stream and combusts them, premoting detonation. If you're turbocharged its even worse because the boost locks the PCV valve shut. At this point, the only place oil vapors can escape the motor is the valve cover vent. If it is routed back into the intake (like before the turbo or on the intake tubing), you're increasing the chance of detonation.
The best way for your performance to handle the stock PCV system is to set it up so that the oil vapors are AT LEAST not going back into the intake or intake manifold. Removing the oil vapors from the intake air stream created by positive crankcase pressure will decrease your chance of detonation, and your mixture will just plain burn better.
The only reason you would want to run the tube to your intake from the valve cover or to your intake manifold from your stock oil separation box is if you're concerned about emissions (i.e., saving the bunny rabbits). If you're worried about saving the bunnies, don't modify your car.
The stock PCV system exists to take pressure and vapors out of the crankcase (both above and below the pistons) and suck it back into the intake manifold. The purpose is so that instead of venting it into the atmoshpere, you are sucking it into the motor with the air from your intake and combusting it (i.e., you burn it off and filter the exhaust with your cat instead of just venting it out into the air).
Stock, its setup for optimum emissions and worst performance. There are 2 general situations this stock PCV sytem can be in: Idle/crusing (vacuum system), and WOT (atmospheric pressurize/perhaps boost).
1) Like someone said previously, the intake manifold has a lower pressure. When you're idling, the vacuum in the IM is higher than that anywhere else in the system, so it draws the oil vapors from the crankcase (both the back of the block and the valve cover) into the intake manifold for combustion. You are sucking up nasty oil vapors and burning them (which premotes detonation). The only upside to having the stock pcv lines hooked into the IM and intake is that the vacuum they provide in the crankcase can actually "pull on" the rings to create a better ring seal. This only improves the ring seal while under vacuum conditions (it doesn't increase your compression or help your rings seal better when you're racing).
2) at WOT, the crankcase becomes pressurized. The valve cover vent and stock separation box (the black box on the back of the block) allow extra pressure from the crankcase to vent into the intake/intake manifold. This extra pressure pushes out the oil vapors into your intake air stream and combusts them, premoting detonation. If you're turbocharged its even worse because the boost locks the PCV valve shut. At this point, the only place oil vapors can escape the motor is the valve cover vent. If it is routed back into the intake (like before the turbo or on the intake tubing), you're increasing the chance of detonation.
The best way for your performance to handle the stock PCV system is to set it up so that the oil vapors are AT LEAST not going back into the intake or intake manifold. Removing the oil vapors from the intake air stream created by positive crankcase pressure will decrease your chance of detonation, and your mixture will just plain burn better.
The only reason you would want to run the tube to your intake from the valve cover or to your intake manifold from your stock oil separation box is if you're concerned about emissions (i.e., saving the bunny rabbits). If you're worried about saving the bunnies, don't modify your car.
The Dealer
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I did this on my car, i had to increase idle slightly or it would die out at stops. my car now idles at the stock level with more smoothness too. BTW, I live in the Los Angeles area, so my car never sees snow. and the performance difference for this simple mod is smoothness, the only power difference is at night, and it's hardly noticeable.
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servion, so my setup with the breather filter on the valve cover is a good setup or should I figure out a way to introduce vacuum into my catch can to allow the PCV valve to be open under boost?
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From: Sacramento, CA.
Originally Posted by servion
Many of you are confused.
The stock PCV system exists to take pressure and vapors out of the crankcase (both above and below the pistons) and suck it back into the intake manifold. The purpose is so that instead of venting it into the atmoshpere, you are sucking it into the motor with the air from your intake and combusting it (i.e., you burn it off and filter the exhaust with your cat instead of just venting it out into the air).
Stock, its setup for optimum emissions and worst performance. There are 2 general situations this stock PCV sytem can be in: Idle/crusing (vacuum system), and WOT (atmospheric pressurize/perhaps boost).
1) Like someone said previously, the intake manifold has a lower pressure. When you're idling, the vacuum in the IM is higher than that anywhere else in the system, so it draws the oil vapors from the crankcase (both the back of the block and the valve cover) into the intake manifold for combustion. You are sucking up nasty oil vapors and burning them (which premotes detonation). The only upside to having the stock pcv lines hooked into the IM and intake is that the vacuum they provide in the crankcase can actually "pull on" the rings to create a better ring seal. This only improves the ring seal while under vacuum conditions (it doesn't increase your compression or help your rings seal better when you're racing).
2) at WOT, the crankcase becomes pressurized. The valve cover vent and stock separation box (the black box on the back of the block) allow extra pressure from the crankcase to vent into the intake/intake manifold. This extra pressure pushes out the oil vapors into your intake air stream and combusts them, premoting detonation. If you're turbocharged its even worse because the boost locks the PCV valve shut. At this point, the only place oil vapors can escape the motor is the valve cover vent. If it is routed back into the intake (like before the turbo or on the intake tubing), you're increasing the chance of detonation.
The best way for your performance to handle the stock PCV system is to set it up so that the oil vapors are AT LEAST not going back into the intake or intake manifold. Removing the oil vapors from the intake air stream created by positive crankcase pressure will decrease your chance of detonation, and your mixture will just plain burn better.
The only reason you would want to run the tube to your intake from the valve cover or to your intake manifold from your stock oil separation box is if you're concerned about emissions (i.e., saving the bunny rabbits). If you're worried about saving the bunnies, don't modify your car.
The stock PCV system exists to take pressure and vapors out of the crankcase (both above and below the pistons) and suck it back into the intake manifold. The purpose is so that instead of venting it into the atmoshpere, you are sucking it into the motor with the air from your intake and combusting it (i.e., you burn it off and filter the exhaust with your cat instead of just venting it out into the air).
Stock, its setup for optimum emissions and worst performance. There are 2 general situations this stock PCV sytem can be in: Idle/crusing (vacuum system), and WOT (atmospheric pressurize/perhaps boost).
1) Like someone said previously, the intake manifold has a lower pressure. When you're idling, the vacuum in the IM is higher than that anywhere else in the system, so it draws the oil vapors from the crankcase (both the back of the block and the valve cover) into the intake manifold for combustion. You are sucking up nasty oil vapors and burning them (which premotes detonation). The only upside to having the stock pcv lines hooked into the IM and intake is that the vacuum they provide in the crankcase can actually "pull on" the rings to create a better ring seal. This only improves the ring seal while under vacuum conditions (it doesn't increase your compression or help your rings seal better when you're racing).
2) at WOT, the crankcase becomes pressurized. The valve cover vent and stock separation box (the black box on the back of the block) allow extra pressure from the crankcase to vent into the intake/intake manifold. This extra pressure pushes out the oil vapors into your intake air stream and combusts them, premoting detonation. If you're turbocharged its even worse because the boost locks the PCV valve shut. At this point, the only place oil vapors can escape the motor is the valve cover vent. If it is routed back into the intake (like before the turbo or on the intake tubing), you're increasing the chance of detonation.
The best way for your performance to handle the stock PCV system is to set it up so that the oil vapors are AT LEAST not going back into the intake or intake manifold. Removing the oil vapors from the intake air stream created by positive crankcase pressure will decrease your chance of detonation, and your mixture will just plain burn better.
The only reason you would want to run the tube to your intake from the valve cover or to your intake manifold from your stock oil separation box is if you're concerned about emissions (i.e., saving the bunny rabbits). If you're worried about saving the bunnies, don't modify your car.
Burning oil vapors is not going to increase chances of detonation. Not only that but the vacuum is not going to make a big enough difference to pull on the rings and change the ring seal...You are smoking rock.
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From: Colorado
Originally Posted by Larry from Endyn
Regardless of piston ring condition, all Honda VTEC engines all suffer from excessive crankcase pressure at high power and RPM levels. This is caused by extreme piston speed, long camshaft timing events, and a PCV system that is completely inadequate at high throttle angles and low manifold vacuum levels.
Many of today's large displacement B series engines are based on new blocks where Honda deleted the breathing "can" (on the rear of the block), causing these engines really suffer from extreme crankcase pressure (frequently high enough to rush past the seals, blowing the spark plug wires off the plugs.) Pressures like these cause oil and other contaminates to severely degrade the quality of the mixture in the cylinders, reducing power and greatly increasing the possibility of detonation.
Many of today's large displacement B series engines are based on new blocks where Honda deleted the breathing "can" (on the rear of the block), causing these engines really suffer from extreme crankcase pressure (frequently high enough to rush past the seals, blowing the spark plug wires off the plugs.) Pressures like these cause oil and other contaminates to severely degrade the quality of the mixture in the cylinders, reducing power and greatly increasing the possibility of detonation.
Do a little research (from credible sources) before you continue to babble on.
