Hose from valve cover to intake-what is it's purpose?
01-03-2011, 03:50 PM
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Hose from valve cover to intake-what is it's purpose?
Alright guys well ive searched and i found mixed answers on the topic
On the valve cover of b series motors there like a spicket that blows air out.'
I've seen people plug up this with a little filter breather and ive also seen a hose go from this to an inlet on the intake?
What are the causes and effects if you have ethier the breather or the hose on their or what if you have nothing on their at all will it do any harm?
Thanks in advance
On the valve cover of b series motors there like a spicket that blows air out.'
I've seen people plug up this with a little filter breather and ive also seen a hose go from this to an inlet on the intake?
What are the causes and effects if you have ethier the breather or the hose on their or what if you have nothing on their at all will it do any harm?
Thanks in advance
01-03-2011, 03:57 PM
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Re: Hose from valve cover to intake-what is it's purpose?
No it wont do any harm not having one, but dirt and other things that you dont want can get inside of ur motor. I recommend putting some thing there. Either a little filter or a hose like its supost to be. Everything is there for a reason.
01-03-2011, 05:32 PM
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Re: Hose from valve cover to intake-what is it's purpose?
It's a fresh air vent for positive crank case ventilation. When the crank case is evacuated by vacuum from the manifold, the air from the vent takes its place.
01-03-2011, 09:17 PM
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Re: Hose from valve cover to intake-what is it's purpose?
i doubt it. only difference is you're pulling air from atmosphere rather than an enclosure that's under vacuum. shouldn't really make a difference in economy
01-04-2011, 05:31 AM
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Re: Hose from valve cover to intake-what is it's purpose?
It's part of the PCV system and can adversely affect piston rings and other things in the long run. I would leave it connected. It's not like it's hurting anything.
I've had my intake arm off the car many times, and have never noticed any more than just slight oil residue in the intake arm, and my car/engine are just coming up on 300K miles.
*edit* great post on Team Integra:
I've had my intake arm off the car many times, and have never noticed any more than just slight oil residue in the intake arm, and my car/engine are just coming up on 300K miles.
*edit* great post on Team Integra:
Originally Posted by SufferX @ Team-Integra.net
The honda crankcase breather is a POSITIVE pressure ventilation system.The air from the intake blows into the valve cover. It is NOT a negative pressure ventilation system...it does NOT suck air from the valvecover to the intake.
Breathers remove the source of positive ventilation that repressurizes the POSTIVE CRANKCASE VENTILATION (PCV) valve.
There is less pressure in the crank when you add a breather at the valve cover. The consequence of this is you get more positive blow-by from the combustion chamber past the piston rings and into the crankcase. More blow-by means less cylinder pressure...less cylinder pressure means the burn is slower and less complete...the result is more emissions and less power.
If you want to do this right and remove oil vapor from the circulating crankcase before it goes into the intake valve then, get an oilcatch can and put a breather on the catch can. Then place the catch can in between the valve cover breather and the PCV valve.
Disconnecting the breather tube, which blows fresh intake air into the valve cover, and placing a breather on the valve cover just creates more blow-by and emissions. Eventually you have so much blow-by, you lose power.
Breathers remove the source of positive ventilation that repressurizes the POSTIVE CRANKCASE VENTILATION (PCV) valve.
There is less pressure in the crank when you add a breather at the valve cover. The consequence of this is you get more positive blow-by from the combustion chamber past the piston rings and into the crankcase. More blow-by means less cylinder pressure...less cylinder pressure means the burn is slower and less complete...the result is more emissions and less power.
If you want to do this right and remove oil vapor from the circulating crankcase before it goes into the intake valve then, get an oilcatch can and put a breather on the catch can. Then place the catch can in between the valve cover breather and the PCV valve.
Disconnecting the breather tube, which blows fresh intake air into the valve cover, and placing a breather on the valve cover just creates more blow-by and emissions. Eventually you have so much blow-by, you lose power.
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01-04-2011, 05:54 AM
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Re: Hose from valve cover to intake-what is it's purpose?
dont just plug it or stick a filter as previously stated
putting a breather will actually restrict the pressure from releasing like it should
01-04-2011, 06:08 AM
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Re: Hose from valve cover to intake-what is it's purpose?
This kind of thing has to be measured so precisely it barely worth it. How you are going to tell without a dyno that you are getting .1 less HP or .1 less MPG?
Those crankcase ventilation things are definitely user moddable. Most of that stuff is regulated so that manufacturer has to be able to say "No crankcase blowby is released to the atmosphere". But really, if you just vent it to the atmosphere you would theoretically improve performance because the engine wouldn't be trying to suck in some unknown fuel/air mixture straight back into the main clean air intake.
If you change something like that you're really getting into an engineering area where you need to take into account the whole system balance and play different factors against each other to achieve the best compromise.
It's tough for Honda engineers in the lab to do this, and make it reliable and servicable and so on....Harder, super hard, to do it on ONE project car and have a real effect.
Those crankcase ventilation things are definitely user moddable. Most of that stuff is regulated so that manufacturer has to be able to say "No crankcase blowby is released to the atmosphere". But really, if you just vent it to the atmosphere you would theoretically improve performance because the engine wouldn't be trying to suck in some unknown fuel/air mixture straight back into the main clean air intake.
If you change something like that you're really getting into an engineering area where you need to take into account the whole system balance and play different factors against each other to achieve the best compromise.
It's tough for Honda engineers in the lab to do this, and make it reliable and servicable and so on....Harder, super hard, to do it on ONE project car and have a real effect.
01-04-2011, 09:38 AM
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Re: Hose from valve cover to intake-what is it's purpose?
This kind of thing has to be measured so precisely it barely worth it. How you are going to tell without a dyno that you are getting .1 less HP or .1 less MPG?
Those crankcase ventilation things are definitely user moddable. Most of that stuff is regulated so that manufacturer has to be able to say "No crankcase blowby is released to the atmosphere". But really, if you just vent it to the atmosphere you would theoretically improve performance because the engine wouldn't be trying to suck in some unknown fuel/air mixture straight back into the main clean air intake.
If you change something like that you're really getting into an engineering area where you need to take into account the whole system balance and play different factors against each other to achieve the best compromise.
It's tough for Honda engineers in the lab to do this, and make it reliable and servicable and so on....Harder, super hard, to do it on ONE project car and have a real effect.
Those crankcase ventilation things are definitely user moddable. Most of that stuff is regulated so that manufacturer has to be able to say "No crankcase blowby is released to the atmosphere". But really, if you just vent it to the atmosphere you would theoretically improve performance because the engine wouldn't be trying to suck in some unknown fuel/air mixture straight back into the main clean air intake.
If you change something like that you're really getting into an engineering area where you need to take into account the whole system balance and play different factors against each other to achieve the best compromise.
It's tough for Honda engineers in the lab to do this, and make it reliable and servicable and so on....Harder, super hard, to do it on ONE project car and have a real effect.
01-04-2011, 08:46 PM
#11
Re: Hose from valve cover to intake-what is it's purpose?
It's part of the PCV system and can adversely affect piston rings and other things in the long run. I would leave it connected. It's not like it's hurting anything.
I've had my intake arm off the car many times, and have never noticed any more than just slight oil residue in the intake arm, and my car/engine are just coming up on 300K miles.
*edit* great post on Team Integra:
I've had my intake arm off the car many times, and have never noticed any more than just slight oil residue in the intake arm, and my car/engine are just coming up on 300K miles.
*edit* great post on Team Integra:
01-04-2011, 09:46 PM
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01-06-2011, 05:40 AM
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Re: Hose from valve cover to intake-what is it's purpose?
Maybe you missed my post above. The tube from the intake to the valve cover is designed to send POSITIVE ventilation from the intake to the valve cover, i.e. air blows into the valve cover and pressurizes it. Without that tube, there is no positive pressure under the valve cover, which can adversely affect the PCV system at removing pressure from the crankcase.
01-06-2011, 05:46 AM
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Re: Hose from valve cover to intake-what is it's purpose?
You DO NOT want to run without a PCV system unless you like blowing gaskets and seals.
01-06-2011, 08:07 AM
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01-06-2011, 08:43 AM
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Re: Hose from valve cover to intake-what is it's purpose?
Ok too complicated to diagnose.
On a hot day, fuel vaporizes and has to be stored in the canister for later.
On cold start, Exhaust Gas cannot be recirculated to combustion chamber, but later it can.
Always the PCV system is what? open? closed? What causes the PCV VALVE to open or close?
So at any given moment, if my engine is not running properly, in addition to doing a tune-up and checking millions of other things, somehow I've got to figure out if maybe the EVAP canister is flooding something, the EGR valve is stuck or something or maybe the PCV is open...it's all just way too 'rigged'.
You can kinda see it looking at the throttle body. It looks more like an old mechanical carb setup than a high-tech computer controlled setup-..
Anyway, it works.
On a hot day, fuel vaporizes and has to be stored in the canister for later.
On cold start, Exhaust Gas cannot be recirculated to combustion chamber, but later it can.
Always the PCV system is what? open? closed? What causes the PCV VALVE to open or close?
So at any given moment, if my engine is not running properly, in addition to doing a tune-up and checking millions of other things, somehow I've got to figure out if maybe the EVAP canister is flooding something, the EGR valve is stuck or something or maybe the PCV is open...it's all just way too 'rigged'.
You can kinda see it looking at the throttle body. It looks more like an old mechanical carb setup than a high-tech computer controlled setup-..
Anyway, it works.
06-16-2019, 03:20 PM
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Re: Hose from valve cover to intake-what is it's purpose?
It's part of the PCV system and can adversely affect piston rings and other things in the long run. I would leave it connected. It's not like it's hurting anything.
I've had my intake arm off the car many times, and have never noticed any more than just slight oil residue in the intake arm, and my car/engine are just coming up on 300K miles.
*edit* great post on Team Integra:
I've had my intake arm off the car many times, and have never noticed any more than just slight oil residue in the intake arm, and my car/engine are just coming up on 300K miles.
*edit* great post on Team Integra:
IS THERE ANYWAY TO DELET THIS HOSE?
06-16-2019, 04:58 PM
#20
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Re: Hose from valve cover to intake-what is it's purpose?
This kind of thing has to be measured so precisely it barely worth it. How you are going to tell without a dyno that you are getting .1 less HP or .1 less MPG?
Those crankcase ventilation things are definitely user moddable. Most of that stuff is regulated so that manufacturer has to be able to say "No crankcase blowby is released to the atmosphere". But really, if you just vent it to the atmosphere you would theoretically improve performance because the engine wouldn't be trying to suck in some unknown fuel/air mixture straight back into the main clean air intake.
If you change something like that you're really getting into an engineering area where you need to take into account the whole system balance and play different factors against each other to achieve the best compromise.
It's tough for Honda engineers in the lab to do this, and make it reliable and servicable and so on....Harder, super hard, to do it on ONE project car and have a real effect.
Those crankcase ventilation things are definitely user moddable. Most of that stuff is regulated so that manufacturer has to be able to say "No crankcase blowby is released to the atmosphere". But really, if you just vent it to the atmosphere you would theoretically improve performance because the engine wouldn't be trying to suck in some unknown fuel/air mixture straight back into the main clean air intake.
If you change something like that you're really getting into an engineering area where you need to take into account the whole system balance and play different factors against each other to achieve the best compromise.
It's tough for Honda engineers in the lab to do this, and make it reliable and servicable and so on....Harder, super hard, to do it on ONE project car and have a real effect.
Yes replace/ delete the stock OEM PCV system with a properly designed catch can system Projectimport.com sells a full bolt on replacement kit for the B series.
06-17-2019, 12:40 PM
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Re: Hose from valve cover to intake-what is it's purpose?
Oh no....got suckered into answering multiple old posts,
Anyways, I'd leave it alone. you're not gaining performance by putting that silly filter thingie on it.
Anyways, I'd leave it alone. you're not gaining performance by putting that silly filter thingie on it.
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