CrankCase filter mod will cause a LEAN condition!!!!
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Senior Member
Joined: Apr 2000
Posts: 215
Likes: 0
From: Ramona Ca
Ok guys, try this. With the truck idling, pull the PVC valve out and see what happens. If nothing then the air is unmetered. But if you look at the PVC tube and where it enters the inlet on top of the blower, where does it gets its air from? The drivers side tube that runs just forward of the TB. Now is the air at the TB already metered or not? Yes it is, if its past the MAF, its metered.
If you look at the system, the air is designed to enter the drivers side valve cover, go through the engine, exit through the PVC valve, then goes into the upper runner on top of the blower. Any air you let in AFTER the MAF that hasn't already been through the MAF and metered, is extra air.
I had this situation happen on my stang (Supercharged) when I changed the plugs I left the PVC out by accident and when I got on it, it pinged like crazy. Pulled over and found the PVC out of the valve cover and installed it and it never pinged again. Simular system in that it is a closed loop system after the MAF.
Just trying to help, if it works for you then go for it. I personally don't think that you should have oil in the TB area, the system is designed to suck form there and exit the PCV valve and back in the top of the blower. If you got oil there, it needs to be fixed.
Just my $.02
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GO HARD OR GO HOME........
*Red 2000 SVT Lightning
*Leer Lo-Rider Bed Cover
*Swanson Performance Chip
*Adopted 3/29/00, #221
*352RWHP / 432RWTQ with Chip
-98 Mustang GT Convertible, Built 4.6L,
Supercharged with FRPP Eaton M112 @ 12psi
To many handling/engine mods to list.....
If you look at the system, the air is designed to enter the drivers side valve cover, go through the engine, exit through the PVC valve, then goes into the upper runner on top of the blower. Any air you let in AFTER the MAF that hasn't already been through the MAF and metered, is extra air.
I had this situation happen on my stang (Supercharged) when I changed the plugs I left the PVC out by accident and when I got on it, it pinged like crazy. Pulled over and found the PVC out of the valve cover and installed it and it never pinged again. Simular system in that it is a closed loop system after the MAF.
Just trying to help, if it works for you then go for it. I personally don't think that you should have oil in the TB area, the system is designed to suck form there and exit the PCV valve and back in the top of the blower. If you got oil there, it needs to be fixed.
Just my $.02
------------------
GO HARD OR GO HOME........
*Red 2000 SVT Lightning
*Leer Lo-Rider Bed Cover
*Swanson Performance Chip
*Adopted 3/29/00, #221
*352RWHP / 432RWTQ with Chip
-98 Mustang GT Convertible, Built 4.6L,
Supercharged with FRPP Eaton M112 @ 12psi
To many handling/engine mods to list.....
Senior Member
Joined: Sep 2000
Posts: 1,636
Likes: 0
From: Olive Branch, MS, Memphis Burb
I did a little experiment tonight to see how this whole system works. The reason you don't really notice any oil around the PCV hose is during acceleration the valve is sucked closed. When it's idling the valve has a strong vacuum. If you pull the hose off of the drivers side valve cover you can feel a vacuum (barely) at idle. If you unplug the PCV at idle then I couldn't tell for sure if there was any vacuum on the drivers side. With the PCV back in, when revving the engine, it felt neutral on the drivers side. I couldn't tell if it was sucking in or blowing out. This explains why it's able to suck so much oil in the tube on the drivers side. It has a big straw with a supercharger sucking on it and no pressure to fight back. The leanest condition would have to be at idle when the butterflies are closed and it's pulling a small amount of air through the valve cover. At part throttle the amount of extra air not even worth talking about. The all important full throttle seems like it gets none at all but if it did it's nothing compared to the amount being sucked in at the intake. With these things running on the rich side I wouldn't worry about it at all. I plan on pulling a plug tommorrow just to see what it looks like.
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Later,
Chuck
Black 00
Chuck's Lightning Page
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Later,
Chuck
Black 00
Chuck's Lightning Page
Senior Member
Joined: Nov 2000
Posts: 723
Likes: 0
From: Proctorville, Ohio
Red2000SVT,
You make good points and you understand very well the flow path of the PCV system through the engine. I also understand why you are saying it's metered.
When a device is hooked up to vacuum below the throttle plates, it pulls strongly at idle and cruise. However, when you push the pedal down, the vacuum falls, meaning the PCV valve will quit sucking, especially at full throttle in this situation. Therefore, metering goes out the window because the PCV won't have the vacuum under these circumstances and won't pull on the filter. In fact, the reverse begins to happen as combustion blowby occurs. That's why they're puking out the covers due to insufficient baffles.
Take for instance a carburetor with a vacuum port above the throttle plates - at idle there's no vacuum, but when the engine speeds up, it creates vacuum because of a venturi-type effect. I think in the first circumstance, we could run lean because of where the PCV valve is at idle. But, I noticed no ill effect in the driveway this evening because of it.
I appreciate your comments. If I'm missing something, please let me know.
------------------
Jim
Black '00
#1,757 built 3/30/00
Clear corners
J.L. Race program
J.L. Stage II ram-air
MagnaFlow Exhaust
[This message has been edited by gforce (edited 02-10-2001).]
You make good points and you understand very well the flow path of the PCV system through the engine. I also understand why you are saying it's metered.
When a device is hooked up to vacuum below the throttle plates, it pulls strongly at idle and cruise. However, when you push the pedal down, the vacuum falls, meaning the PCV valve will quit sucking, especially at full throttle in this situation. Therefore, metering goes out the window because the PCV won't have the vacuum under these circumstances and won't pull on the filter. In fact, the reverse begins to happen as combustion blowby occurs. That's why they're puking out the covers due to insufficient baffles.
Take for instance a carburetor with a vacuum port above the throttle plates - at idle there's no vacuum, but when the engine speeds up, it creates vacuum because of a venturi-type effect. I think in the first circumstance, we could run lean because of where the PCV valve is at idle. But, I noticed no ill effect in the driveway this evening because of it.
I appreciate your comments. If I'm missing something, please let me know.
------------------
Jim
Black '00
#1,757 built 3/30/00
Clear corners
J.L. Race program
J.L. Stage II ram-air
MagnaFlow Exhaust
[This message has been edited by gforce (edited 02-10-2001).]
Senior Member
Joined: Oct 2000
Posts: 668
Likes: 0
From: Mi.
I hate to say what im going to say because then people think of you as a know it all!!
Here i go! The PCM attepts to maintain an air/fuel ratio of 14.7:1 during acceleration.
In order for the PCM to supply the correct amount of fuel it needs to know the amount of air entering the engine ok! Air is known to consist of 21% oxygen. tempature and pressure are also factors.
After the PCM knows the concentration of oxygen in each foot of air it calculates the exact amount of fuel. The PCV is not looked at as a air source. Red2000SVT i understand what you are saying. The strategy in the PCM already has calculations to determine the correct amount of air present.
PCM knows because the MAF sensor directly reads the air mass going into the engine. Not temp,volume or pressure. The maf is based on heat absorption. Each molecule of air is capable of absorbing a specific amount of heat. The MAF uses the heat as it's basis for determining the amount of oxygen into the engine. I'm going to stop here!
If anyone is interested in knowing how the MAF works send another reply. I'll continue! Along with Fuel control. The amount of fuel added to your engine is not based on the PCV or vent tube on the drivers side. It's only for emissions.
Thor01
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2001 L. (Silver)
Born on date: 1/17/01
Weight: 4,670 lb.
Eyes: Clear
Blood type: Ford Blue
Received: 1/25/01
Here i go! The PCM attepts to maintain an air/fuel ratio of 14.7:1 during acceleration.
In order for the PCM to supply the correct amount of fuel it needs to know the amount of air entering the engine ok! Air is known to consist of 21% oxygen. tempature and pressure are also factors.
After the PCM knows the concentration of oxygen in each foot of air it calculates the exact amount of fuel. The PCV is not looked at as a air source. Red2000SVT i understand what you are saying. The strategy in the PCM already has calculations to determine the correct amount of air present.
PCM knows because the MAF sensor directly reads the air mass going into the engine. Not temp,volume or pressure. The maf is based on heat absorption. Each molecule of air is capable of absorbing a specific amount of heat. The MAF uses the heat as it's basis for determining the amount of oxygen into the engine. I'm going to stop here!
If anyone is interested in knowing how the MAF works send another reply. I'll continue! Along with Fuel control. The amount of fuel added to your engine is not based on the PCV or vent tube on the drivers side. It's only for emissions.
Thor01
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2001 L. (Silver)
Born on date: 1/17/01
Weight: 4,670 lb.
Eyes: Clear
Blood type: Ford Blue
Received: 1/25/01
Senior Member
Joined: Jan 2001
Posts: 139
Likes: 0
From: Portland,Oregon,United states
Positive crankcase ventilation is a good thing.
Mark_2kl had a great idea using a "puke can"
Another idea for those of you who are smart enough to know you should run a PCV system ..... how about splicing in an Oil/Water separater in the PCV line. You know ..... the kind auto body and paint shops run in their compressed air supply lines. If I was gonna do that, I would mount the separater down low ... by the frame or something.
So either way, "Sealed puke can" or a "oil/water" separator would cure the problem of oil mist getting into the intake system and gooing up the intercooler fins, and at the same time it would properly evacuate the crankcase.
Just my 2 cents worth on this WAY too long of a thread
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Cars and Trucks are made to be driven. NOT worshiped
Mark_2kl had a great idea using a "puke can"
Another idea for those of you who are smart enough to know you should run a PCV system ..... how about splicing in an Oil/Water separater in the PCV line. You know ..... the kind auto body and paint shops run in their compressed air supply lines. If I was gonna do that, I would mount the separater down low ... by the frame or something.
So either way, "Sealed puke can" or a "oil/water" separator would cure the problem of oil mist getting into the intake system and gooing up the intercooler fins, and at the same time it would properly evacuate the crankcase.
Just my 2 cents worth on this WAY too long of a thread
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Cars and Trucks are made to be driven. NOT worshiped
Senior Member
Joined: Oct 2000
Posts: 668
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From: Mi.
Lightfootning,
I'm not smart enough? Why don't you put it in Engineering terms so I do understand! I work at Ford as a Prototype Engineering Technologist! I think I will understand. You gave no reason why it would be smart!
Please elaborate a little more! Just for humors sake I worked for Jack Roush here in Livonia for five years and none of his NASCAR engines had a "POSITIVE CRANKCASE VENTALEATION VALVE"
You gain nothing breathing in oil vapor to your intercooler! The only reason the manufacturers have them on the cars is b/c emission regulations. Can't vent oil vapor into the atmosphere! So why is it smart? Basics, an engine is just an AIR PUMP!! So, please tell!!
------------------
2001 L. (Silver)
Born on date: 1/17/01
Weight: 4,670 lb.
Eyes: Clear
Blood type: Ford Blue
Received: 1/25/01
I'm not smart enough? Why don't you put it in Engineering terms so I do understand! I work at Ford as a Prototype Engineering Technologist! I think I will understand. You gave no reason why it would be smart!
Please elaborate a little more! Just for humors sake
I worked for Jack Roush here in Livonia for five years and none of his NASCAR engines had a "POSITIVE CRANKCASE VENTALEATION VALVE" You gain nothing breathing in oil vapor to your intercooler! The only reason the manufacturers have them on the cars is b/c emission regulations. Can't vent oil vapor into the atmosphere! So why is it smart? Basics, an engine is just an AIR PUMP!! So, please tell!!
------------------
2001 L. (Silver)
Born on date: 1/17/01
Weight: 4,670 lb.
Eyes: Clear
Blood type: Ford Blue
Received: 1/25/01
Senior Member
Joined: Sep 2000
Posts: 1,636
Likes: 0
From: Olive Branch, MS, Memphis Burb
Thor01,
Thanks for confirming what most of us thought. We figured the small amount of extra air sucked in by a drivers side filter at idle and cruise was a non-issue.
------------------
Later,
Chuck
Black 00
Chuck's Lightning Page
Thanks for confirming what most of us thought. We figured the small amount of extra air sucked in by a drivers side filter at idle and cruise was a non-issue.
------------------
Later,
Chuck
Black 00
Chuck's Lightning Page
Senior Member
Joined: Aug 2000
Posts: 314
Likes: 0
From: Irving, Texas
The engineers that report here know that pressure and volume are too different things....I would jesture j/k to say that this would have a minimal effect on volumetric air intake into cylinder bore area...I would have never thought any negative hoopla regarding a breather...breathers are Pre-EPA stuff...when you could rebuild a Holley blindfolded......bummer...the good ol' days.. 
: reduced contaminants introduced into the air intake system of the motor..
[This message has been edited by whitelightnin' (edited 02-10-2001).]
: reduced contaminants introduced into the air intake system of the motor.. [This message has been edited by whitelightnin' (edited 02-10-2001).]
Senior Member
Joined: Jan 2001
Posts: 139
Likes: 0
From: Portland,Oregon,United states
Thor01,
Your right, as far as performance goes .. positive crankcase ventilation is a non issue.
Where I was coming from was from the point of an everyday driver ... you know 140,000 mile in 10/15 years and not pulling the motor every spring to freshen it up.
My 1950 olds had an old prehistoric style crankcase evac system on it. It had a pipe going from the valve cover down to the lower engine compartment, just a bit above the road. As you drove along the the air passing over the end of the pipe would create a vacume, thus pulling out the vapors and plastering the oil all over the road. ha ha ha. Take a look at old pictures from the late 60's of our freeways ...... you will notice a dark black line down the center of the road from the old style evac systems. That was pre emmission days ........ and car makers still wanted to evac the crankcase .... hmmm
I thought the whole point behind crankcase ventilation was so that the engine would not get all sludged up and gooey like the inside of your glass fireplace door or the glass on the oven door
I guess this day and age with synthetic oils with high detergents it may not be a problem anymore.
I apologize for my backward thinking in that I thought that the system was for keeping the insides of my engine clean. I gotta go find my old shop teacher and give him a slap upside the head for filling my mind with that crapola.
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Cars and Trucks are made to be driven. NOT worshiped
Your right, as far as performance goes .. positive crankcase ventilation is a non issue.
Where I was coming from was from the point of an everyday driver ... you know 140,000 mile in 10/15 years and not pulling the motor every spring to freshen it up.
My 1950 olds had an old prehistoric style crankcase evac system on it. It had a pipe going from the valve cover down to the lower engine compartment, just a bit above the road. As you drove along the the air passing over the end of the pipe would create a vacume, thus pulling out the vapors and plastering the oil all over the road. ha ha ha. Take a look at old pictures from the late 60's of our freeways ...... you will notice a dark black line down the center of the road from the old style evac systems. That was pre emmission days ........ and car makers still wanted to evac the crankcase .... hmmm
I thought the whole point behind crankcase ventilation was so that the engine would not get all sludged up and gooey like the inside of your glass fireplace door or the glass on the oven door
I guess this day and age with synthetic oils with high detergents it may not be a problem anymore.
I apologize for my backward thinking in that I thought that the system was for keeping the insides of my engine clean. I gotta go find my old shop teacher and give him a slap upside the head for filling my mind with that crapola.
------------------
Cars and Trucks are made to be driven. NOT worshiped
Member
Joined: Dec 2000
Posts: 67
Likes: 0
From: Macomb,MI. USA
Everybody - Cool down on this subject - we can all get into the technical aspect of the subject - BUT - seat of the pants is the only true way of knowing what to expect! I propose that East meets West (cold weather vs. warm weather) to really see if this fix will work. Anyone who races could report on if the I/C leaks etc. Possibly two items of concern could be eliminated.
Cruiser
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'00 White Lightning
#39 of 4966/built 2/2/00
API trans chip
ASP 2# blower pulley
K&N filter (stock box)
JL ram air (modified)
Borla exhaust
Cruiser
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'00 White Lightning
#39 of 4966/built 2/2/00
API trans chip
ASP 2# blower pulley
K&N filter (stock box)
JL ram air (modified)
Borla exhaust
Senior Member
Joined: Jan 2001
Posts: 139
Likes: 0
From: Portland,Oregon,United states
Thor01,
Did your old dad tell you the one about using strips of leather for rod bearings during the war when parts were impossible to get ? If he did, then perhaps he knows my old shop teacher ?
Well I am off to work, ... Sunshine, cold, detroit big bore, gonna be a good day
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Cars and Trucks are made to be driven. NOT worshiped
Did your old dad tell you the one about using strips of leather for rod bearings during the war when parts were impossible to get ? If he did, then perhaps he knows my old shop teacher ?
Well I am off to work, ... Sunshine, cold, detroit big bore, gonna be a good day
------------------
Cars and Trucks are made to be driven. NOT worshiped
Senior Member
Joined: Oct 2000
Posts: 668
Likes: 0
From: Mi.
Lightfootning,
I didn't take it to heart! I knew what you ment thats why I posted s-faces. I hear my dad talk about the way the cars used to be! He's 70 and a retired engineer from Ford. We could sit talk cars and I still have much of his car literature from the old days. Gaping points with a match-book. No on went far with out an extra set of points in the glove box. I understand, and you don't have to smack your shopteacher when you see him.
------------------
2001 L. (Silver)
Born on date: 1/17/01
Weight: 4,670 lb.
Eyes: Clear
Blood type: Ford Blue
Received: 1/25/01
I didn't take it to heart! I knew what you ment thats why I posted s-faces. I hear my dad talk about the way the cars used to be! He's 70 and a retired engineer from Ford. We could sit talk cars and I still have much of his car literature from the old days. Gaping points with a match-book. No on went far with out an extra set of points in the glove box.
I understand, and you don't have to smack your shopteacher when you see him. ------------------
2001 L. (Silver)
Born on date: 1/17/01
Weight: 4,670 lb.
Eyes: Clear
Blood type: Ford Blue
Received: 1/25/01