What does this do? Oil can catch
05-01-2008, 05:47 PM
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What does this do? Oil can catch
i just got my new Greddy can catch last weekend ...i wanted to install it but it seems like i need to drill some holes because i cant find a suitable place to out it ....and i found something that comes with it ...i dont know where to put this ? does anyone have Greddy oil can catch tell me what's the use of this thing ?
05-01-2008, 09:21 PM
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...for a rotary? You probably wasted your money dude.
In a piston engine, air from the crankcase is vented back into the air intake due to blowby (PCV system). Under high loads this air can be contaminated with lots of oil which can cause carbon buildup, mess up sensors in the intake tract, etc. The catch can is designed to help separate air from oil on it's way back to the intake. In racing engines you often times see this vented to the atmosphere, but it makes your car smell like oil.
But I don't believe that the 8 even has any sort of venting system (though it does have an air valve for the intake) so you're probably not going to get much use out of the thing.
In a piston engine, air from the crankcase is vented back into the air intake due to blowby (PCV system). Under high loads this air can be contaminated with lots of oil which can cause carbon buildup, mess up sensors in the intake tract, etc. The catch can is designed to help separate air from oil on it's way back to the intake. In racing engines you often times see this vented to the atmosphere, but it makes your car smell like oil.
But I don't believe that the 8 even has any sort of venting system (though it does have an air valve for the intake) so you're probably not going to get much use out of the thing.
05-01-2008, 10:16 PM
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^^ yeah, but whats the point?
just because everyone jumps off a cliff, don't mean you got to. j/k
very sorry for using that... i've just been wanting to say that for a while. but check this out:
PCV has more than a few purpose. a) relieve pressure from crankcase b) oil vapors also acts as lube for TB, valves, and other moving emission valves in intake tract c) lower HC in atmosphere d) and i forgot this one... but it has something to do with offsetting crankcase pressure for the benefit of the ring lands and piston rings from certain damage... just to name a few.may be the same as example A.
now what is the catch can's job is simply to collect excess oil vapors... in the case where u run the car real hard in racing applications to see that much oil burn off, or you love to overfill your oil and it gets in your intake( there's a thread with a few who have this case, but there's a revised oil filler neck on newer models to cure that and the "foamy" dipstick symptom)
imo, there's no HUGE benefit in using it. and i doubt the people who does use the catch can aren't routing the catch tank back to the manifold either way. and there's the added weight, so thats my take on it.
plus, how many running it will actually even catch at least 1/2 an ounce in the duration of an oil change interval?
its not as bad as an "crankcase vent filter", and trust me i was once an idiot too until i learned the truth. just as long as you don't senselessly remove oil vent tubes and purge all oil vapors into the atmosphere. you won't gain horsepower, but may lose some.
just because everyone jumps off a cliff, don't mean you got to. j/k
very sorry for using that... i've just been wanting to say that for a while. but check this out:
PCV has more than a few purpose. a) relieve pressure from crankcase b) oil vapors also acts as lube for TB, valves, and other moving emission valves in intake tract c) lower HC in atmosphere d) and i forgot this one... but it has something to do with offsetting crankcase pressure for the benefit of the ring lands and piston rings from certain damage... just to name a few.may be the same as example A.
now what is the catch can's job is simply to collect excess oil vapors... in the case where u run the car real hard in racing applications to see that much oil burn off, or you love to overfill your oil and it gets in your intake( there's a thread with a few who have this case, but there's a revised oil filler neck on newer models to cure that and the "foamy" dipstick symptom)
imo, there's no HUGE benefit in using it. and i doubt the people who does use the catch can aren't routing the catch tank back to the manifold either way. and there's the added weight, so thats my take on it.
plus, how many running it will actually even catch at least 1/2 an ounce in the duration of an oil change interval?
its not as bad as an "crankcase vent filter", and trust me i was once an idiot too until i learned the truth. just as long as you don't senselessly remove oil vent tubes and purge all oil vapors into the atmosphere. you won't gain horsepower, but may lose some.
05-01-2008, 10:18 PM
#6
...for a rotary? You probably wasted your money dude.
In a piston engine, air from the crankcase is vented back into the air intake due to blowby (PCV system). Under high loads this air can be contaminated with lots of oil which can cause carbon buildup, mess up sensors in the intake tract, etc. The catch can is designed to help separate air from oil on it's way back to the intake. In racing engines you often times see this vented to the atmosphere, but it makes your car smell like oil.
But I don't believe that the 8 even has any sort of venting system (though it does have an air valve for the intake) so you're probably not going to get much use out of the thing.
In a piston engine, air from the crankcase is vented back into the air intake due to blowby (PCV system). Under high loads this air can be contaminated with lots of oil which can cause carbon buildup, mess up sensors in the intake tract, etc. The catch can is designed to help separate air from oil on it's way back to the intake. In racing engines you often times see this vented to the atmosphere, but it makes your car smell like oil.
But I don't believe that the 8 even has any sort of venting system (though it does have an air valve for the intake) so you're probably not going to get much use out of the thing.
you seems pretty knowledgeable but you've failed on this one.
Read Maz's reply
05-01-2008, 10:23 PM
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that thing looks like a plug for the intake accordion tube...
really hope you're not trying to vent oil into the atmosphere.
in which case there's no gains, just loses...
think about it. unlike the leaded fuel days where LEAD is a degree of lubrication for the valves, the oil vapor we route back into the intake can be that lubrication substitute to a degree while keeping emissions down.
please mod wisely. =)
really hope you're not trying to vent oil into the atmosphere.
in which case there's no gains, just loses...
think about it. unlike the leaded fuel days where LEAD is a degree of lubrication for the valves, the oil vapor we route back into the intake can be that lubrication substitute to a degree while keeping emissions down.
please mod wisely. =)
05-02-2008, 10:57 AM
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This is my understanding of what's going on: In a piston engine, a certain amount of gasses from above the piston "blowby" the piston rings during a combustion event. You cannot perfectly seal the combustion chamber without raising friction exponentially and making much less power. Under racing loads in a performance engine, these explosions will all be alot larger than just driving around on the highway, and since your sealing isn't increasing (piston ring to chamber wall), more blowby will occur. These combustion gasses that are "blowing by" into the crankcase have carbon and oil, un catalyzed noxoius gasses, etc. This causes an increase in air pressure in the crankcase which can cause alot of problems (most obviously it would be harder for the pistons to travel). This is a bigger issue in forced induction motors btw. They get mixed in with the oil, and it's a whole big mess (coincidentally, carbon from blowby is one of the big reasons your oil turns black). So these gasses are vented back up into the intake tract so they can taken back into the combustion chamber and properly combusted, catalyzed, maintain correct pressure in the crankcase, etc. Venting them straight back to the intake does a few things that are bad though 1: you're introducing nasty low oxygen content combusted fumes back into your nice cool oxygen rich intake charge 2: you're bringing dirty carbon and oil filled soot back into the intake tract 3. sensors or equipment installed (manifold pressure sensors, etc) can be distrupted or suffer premature wear. This is where catch cans come in, they are designed to help pull the oil part of the nasty venting out, and keep the air intake clean. They also make air/oil seperators, and lots of people make them themselves and put in more filtration to make the air even cleaner.
Here's a pic of a catch can at work:
As you can see, the air coming up from the crankcase is dark and sooty, but this guy installed a catch can (filled with stainless steel wool) and as the air comes out to the intake, its no longer filled with soot.
That's the general idea behind what the catch can does (as I've come to understand it).
Now, why do I think it's not really useful in a rotary motor?
Well where do blowby gasses go in the rotor housings? They don't go shooting straight down into the oil pan that's for sure. They most often go to the other sides of the rotor. The oil gets contaminated with soot and other particulate matter, but the air factor really isn't involved in a place where it can be vented. And by the time the oil leaves the combustion chamber and is in a place where it could be vented back to the intake tract, it's not really an issue to worry about beyond what the factory has already done. The soot thing is an issue, but unless you're running a can that's going to actively pull the soot out (like this guy did, he cut the can in half and stuck in SS wool to attract the oil and soot to, then routed the inlet pipe into the can down to the bottom so it would come up though the wool and exit at the top), you're not going to stop much with a regular catch can as they are usually just hollow inside though some have more elaborate filtration...
that thing looks like a plug for the intake accordion tube...
really hope you're not trying to vent oil into the atmosphere.
in which case there's no gains, just loses...
think about it. unlike the leaded fuel days where LEAD is a degree of lubrication for the valves, the oil vapor we route back into the intake can be that lubrication substitute to a degree while keeping emissions down.
please mod wisely. =)
really hope you're not trying to vent oil into the atmosphere.
in which case there's no gains, just loses...
think about it. unlike the leaded fuel days where LEAD is a degree of lubrication for the valves, the oil vapor we route back into the intake can be that lubrication substitute to a degree while keeping emissions down.
please mod wisely. =)
And as far as atmospheric venting causing power losses... once again I don't know where you got this idea. What would be the point in an engine designed for absolute power, that's going to be rebuilt after less than 250 hours of running, to have dirty oil contaminated air taking up space in your precious intake charge? You're just trying to keep the crankcase pressure down, so put it into the atmosphere. Ever wonder what these were for on a motor?
http://store.summitracing.com/partde...5&autoview=sku
Perhaps the stock ECU of a modern road car might have trouble coping with the vacuum changes, but like I said, it's for racing so you should be on a standalone ecu. It makes the car smell of oil and that doesn't go over well with the ladies.
Now that I've ranted and typed for 2 hours at my work, I need a cookie.
Last edited by BMonkey; 05-02-2008 at 11:34 AM.
05-02-2008, 11:20 AM
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i bought it not because i need it ..i know there is no gain in it....its just INCASE the oil goes back into the intake...as a precaution ...i seen threads where the oil messes up the intakes ....especially on the 8 ...with or without FI.....i drive my car normally+a little hard sometimes ...and thought it would be great to have it since i dont want to mess up my intake ....
Last edited by luv4eternity; 05-02-2008 at 11:28 AM.
05-02-2008, 12:03 PM
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^...............correct, that's why people use it and had BMonkey looked before replying he would've seen that people are not using it to catch vapors or anything else, besides keep possible blow back out of the intake. I'm not addressing whether it's valid or not, but I've seen some intakes with a lot of oil blown back in them......so there is some valid use.
05-02-2008, 12:16 PM
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^...............correct, that's why people use it and had BMonkey looked before replying he would've seen that people are not using it to catch vapors or anything else, besides keep possible blow back out of the intake. I'm not addressing whether it's valid or not, but I've seen some intakes with a lot of oil blown back in them......so there is some valid use.
05-02-2008, 12:24 PM
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I thought they did? Not picking on you or anything, but here are some weak examples.
http://www.streetunit.com/GReddy_Oil...p/12003510.htm
http://www.optionimports.com/oilcatchcan.html
Quickiest I could find using at 2 second search.
Anyway...............I learn sumtin on here everday........even in the lounge!
http://www.streetunit.com/GReddy_Oil...p/12003510.htm
http://www.optionimports.com/oilcatchcan.html
Quickiest I could find using at 2 second search.
Anyway...............I learn sumtin on here everday........even in the lounge!
05-02-2008, 01:03 PM
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I didn't fail anything. For a rotary it doesn't really have much purpose.
This is my understanding of what's going on: In a piston engine, a certain amount of gasses from above the piston "blowby" the piston rings during a combustion event. You cannot perfectly seal the combustion chamber without raising friction exponentially and making much less power. Under racing loads in a performance engine, these explosions will all be alot larger than just driving around on the highway, and since your sealing isn't increasing (piston ring to chamber wall), more blowby will occur. These combustion gasses that are "blowing by" into the crankcase have carbon and oil, un catalyzed noxoius gasses, etc. This causes an increase in air pressure in the crankcase which can cause alot of problems (most obviously it would be harder for the pistons to travel). This is a bigger issue in forced induction motors btw. They get mixed in with the oil, and it's a whole big mess (coincidentally, carbon from blowby is one of the big reasons your oil turns black). So these gasses are vented back up into the intake tract so they can taken back into the combustion chamber and properly combusted, catalyzed, maintain correct pressure in the crankcase, etc. Venting them straight back to the intake does a few things that are bad though 1: you're introducing nasty low oxygen content combusted fumes back into your nice cool oxygen rich intake charge 2: you're bringing dirty carbon and oil filled soot back into the intake tract 3. sensors or equipment installed (manifold pressure sensors, etc) can be distrupted or suffer premature wear. This is where catch cans come in, they are designed to help pull the oil part of the nasty venting out, and keep the air intake clean. They also make air/oil seperators, and lots of people make them themselves and put in more filtration to make the air even cleaner.
Here's a pic of a catch can at work:
As you can see, the air coming up from the crankcase is dark and sooty, but this guy installed a catch can (filled with stainless steel wool) and as the air comes out to the intake, its no longer filled with soot.
That's the general idea behind what the catch can does (as I've come to understand it).
Now, why do I think it's not really useful in a rotary motor?
Well where do blowby gasses go in the rotor housings? They don't go shooting straight down into the oil pan that's for sure. They most often go to the other sides of the rotor. The oil gets contaminated with soot and other particulate matter, but the air factor really isn't involved in a place where it can be vented. And by the time the oil leaves the combustion chamber and is in a place where it could be vented back to the intake tract, it's not really an issue to worry about beyond what the factory has already done. The soot thing is an issue, but unless you're running a can that's going to actively pull the soot out (like this guy did, he cut the can in half and stuck in SS wool to attract the oil and soot to, then routed the inlet pipe into the can down to the bottom so it would come up though the wool and exit at the top), you're not going to stop much with a regular catch can as they are usually just hollow inside though some have more elaborate filtration...
Where you got the notion that particulate matter was a lubricant I can't even begin to guess... Anyways, the engineers didn't intend for oil to act as a lubricant in the intake system, that's crap. Motors are designed for all driving conditions and if someone baby's the car for 100k miles, runs MMO and synthetic oil (which would minimize blowby even more), they won't get much blowby at all (piston engine we're talking here). Does this mean that their TB's wont be "lubricated" correctly? Nope.
And as far as atmospheric venting causing power losses... once again I don't know where you got this idea. What would be the point in an engine designed for absolute power, that's going to be rebuilt after less than 250 hours of running, to have dirty oil contaminated air taking up space in your precious intake charge? You're just trying to keep the crankcase pressure down, so put it into the atmosphere. Ever wonder what these were for on a motor?
http://store.summitracing.com/partde...5&autoview=sku
Perhaps the stock ECU of a modern road car might have trouble coping with the vacuum changes, but like I said, it's for racing so you should be on a standalone ecu. It makes the car smell of oil and that doesn't go over well with the ladies.
Now that I've ranted and typed for 2 hours at my work, I need a cookie.
This is my understanding of what's going on: In a piston engine, a certain amount of gasses from above the piston "blowby" the piston rings during a combustion event. You cannot perfectly seal the combustion chamber without raising friction exponentially and making much less power. Under racing loads in a performance engine, these explosions will all be alot larger than just driving around on the highway, and since your sealing isn't increasing (piston ring to chamber wall), more blowby will occur. These combustion gasses that are "blowing by" into the crankcase have carbon and oil, un catalyzed noxoius gasses, etc. This causes an increase in air pressure in the crankcase which can cause alot of problems (most obviously it would be harder for the pistons to travel). This is a bigger issue in forced induction motors btw. They get mixed in with the oil, and it's a whole big mess (coincidentally, carbon from blowby is one of the big reasons your oil turns black). So these gasses are vented back up into the intake tract so they can taken back into the combustion chamber and properly combusted, catalyzed, maintain correct pressure in the crankcase, etc. Venting them straight back to the intake does a few things that are bad though 1: you're introducing nasty low oxygen content combusted fumes back into your nice cool oxygen rich intake charge 2: you're bringing dirty carbon and oil filled soot back into the intake tract 3. sensors or equipment installed (manifold pressure sensors, etc) can be distrupted or suffer premature wear. This is where catch cans come in, they are designed to help pull the oil part of the nasty venting out, and keep the air intake clean. They also make air/oil seperators, and lots of people make them themselves and put in more filtration to make the air even cleaner.
Here's a pic of a catch can at work:
As you can see, the air coming up from the crankcase is dark and sooty, but this guy installed a catch can (filled with stainless steel wool) and as the air comes out to the intake, its no longer filled with soot.
That's the general idea behind what the catch can does (as I've come to understand it).
Now, why do I think it's not really useful in a rotary motor?
Well where do blowby gasses go in the rotor housings? They don't go shooting straight down into the oil pan that's for sure. They most often go to the other sides of the rotor. The oil gets contaminated with soot and other particulate matter, but the air factor really isn't involved in a place where it can be vented. And by the time the oil leaves the combustion chamber and is in a place where it could be vented back to the intake tract, it's not really an issue to worry about beyond what the factory has already done. The soot thing is an issue, but unless you're running a can that's going to actively pull the soot out (like this guy did, he cut the can in half and stuck in SS wool to attract the oil and soot to, then routed the inlet pipe into the can down to the bottom so it would come up though the wool and exit at the top), you're not going to stop much with a regular catch can as they are usually just hollow inside though some have more elaborate filtration...
Where you got the notion that particulate matter was a lubricant I can't even begin to guess... Anyways, the engineers didn't intend for oil to act as a lubricant in the intake system, that's crap. Motors are designed for all driving conditions and if someone baby's the car for 100k miles, runs MMO and synthetic oil (which would minimize blowby even more), they won't get much blowby at all (piston engine we're talking here). Does this mean that their TB's wont be "lubricated" correctly? Nope.
And as far as atmospheric venting causing power losses... once again I don't know where you got this idea. What would be the point in an engine designed for absolute power, that's going to be rebuilt after less than 250 hours of running, to have dirty oil contaminated air taking up space in your precious intake charge? You're just trying to keep the crankcase pressure down, so put it into the atmosphere. Ever wonder what these were for on a motor?
http://store.summitracing.com/partde...5&autoview=sku
Perhaps the stock ECU of a modern road car might have trouble coping with the vacuum changes, but like I said, it's for racing so you should be on a standalone ecu. It makes the car smell of oil and that doesn't go over well with the ladies.
Now that I've ranted and typed for 2 hours at my work, I need a cookie.
sure, with the way you have your oil catch can routed, its nothing fancy but "a break in the line" where a "can" can be used to catch perhaps an overflow of oil for whatever reason it is that it overflow from the crankcase( but obvious there are cases in threads around here about overfill oil going into the intake, BEFORE the revised oil tubes in newer models) maybe useful for motor oil thats over-filled.
but,
-one module exercise was to check PCV operation. which was to pull pcv valve out and check for proper spring play under vacuum, which will create a clicking sound when u put your finger over the opening.
why would you even recommend anyone to use this in their modern cars?
even hot rod shows with motor swaps have a recommendation to fabricate the old style type valve covers to run PCV instead of without.
summit racing only sells products, but they don't need to educate every consumer of its proper use.
so please don't tell me you have ceramic headers and ALSO have it heatwrapped!!!
but, MAYBE YOU"RE RIGHT. if you don't know where i get my ideas, and maybe that it somehow doesn't make sense on one make of cars on others... i can just as well be wrong. but starting off with info from an valid automaker's training background does help me in not making the same mistakes again.... especially in the installation of a ricer breather filter thats of no use on a honda valve cover.
like i said, i was once an idiot too. how anyone here takes my opinion is up to them. if they are smarter or more trained, go right ahead and enlighten me.
05-02-2008, 01:18 PM
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I didn't fail anything. For a rotary it doesn't really have much purpose.
This is my understanding of what's going on: In a piston engine, a certain amount of gasses from above the piston "blowby" the piston rings during a combustion event. You cannot perfectly seal the combustion chamber without raising friction exponentially and making much less power. Under racing loads in a performance engine, these explosions will all be alot larger than just driving around on the highway, and since your sealing isn't increasing (piston ring to chamber wall), more blowby will occur. These combustion gasses that are "blowing by" into the crankcase have carbon and oil, un catalyzed noxoius gasses, etc. This causes an increase in air pressure in the crankcase which can cause alot of problems (most obviously it would be harder for the pistons to travel). This is a bigger issue in forced induction motors btw. They get mixed in with the oil, and it's a whole big mess (coincidentally, carbon from blowby is one of the big reasons your oil turns black). So these gasses are vented back up into the intake tract so they can taken back into the combustion chamber and properly combusted, catalyzed, maintain correct pressure in the crankcase, etc. Venting them straight back to the intake does a few things that are bad though 1: you're introducing nasty low oxygen content combusted fumes back into your nice cool oxygen rich intake charge 2: you're bringing dirty carbon and oil filled soot back into the intake tract 3. sensors or equipment installed (manifold pressure sensors, etc) can be distrupted or suffer premature wear. This is where catch cans come in, they are designed to help pull the oil part of the nasty venting out, and keep the air intake clean. They also make air/oil seperators, and lots of people make them themselves and put in more filtration to make the air even cleaner.
Here's a pic of a catch can at work:
As you can see, the air coming up from the crankcase is dark and sooty, but this guy installed a catch can (filled with stainless steel wool) and as the air comes out to the intake, its no longer filled with soot.
That's the general idea behind what the catch can does (as I've come to understand it).
Now, why do I think it's not really useful in a rotary motor?
Well where do blowby gasses go in the rotor housings? They don't go shooting straight down into the oil pan that's for sure. They most often go to the other sides of the rotor. The oil gets contaminated with soot and other particulate matter, but the air factor really isn't involved in a place where it can be vented. And by the time the oil leaves the combustion chamber and is in a place where it could be vented back to the intake tract, it's not really an issue to worry about beyond what the factory has already done. The soot thing is an issue, but unless you're running a can that's going to actively pull the soot out (like this guy did, he cut the can in half and stuck in SS wool to attract the oil and soot to, then routed the inlet pipe into the can down to the bottom so it would come up though the wool and exit at the top), you're not going to stop much with a regular catch can as they are usually just hollow inside though some have more elaborate filtration...
Where you got the notion that particulate matter was a lubricant I can't even begin to guess... Anyways, the engineers didn't intend for oil to act as a lubricant in the intake system, that's crap. Motors are designed for all driving conditions and if someone baby's the car for 100k miles, runs MMO and synthetic oil (which would minimize blowby even more), they won't get much blowby at all (piston engine we're talking here). Does this mean that their TB's wont be "lubricated" correctly? Nope.
And as far as atmospheric venting causing power losses... once again I don't know where you got this idea. What would be the point in an engine designed for absolute power, that's going to be rebuilt after less than 250 hours of running, to have dirty oil contaminated air taking up space in your precious intake charge? You're just trying to keep the crankcase pressure down, so put it into the atmosphere. Ever wonder what these were for on a motor?
http://store.summitracing.com/partde...5&autoview=sku
Perhaps the stock ECU of a modern road car might have trouble coping with the vacuum changes, but like I said, it's for racing so you should be on a standalone ecu. It makes the car smell of oil and that doesn't go over well with the ladies.
Now that I've ranted and typed for 2 hours at my work, I need a cookie.
This is my understanding of what's going on: In a piston engine, a certain amount of gasses from above the piston "blowby" the piston rings during a combustion event. You cannot perfectly seal the combustion chamber without raising friction exponentially and making much less power. Under racing loads in a performance engine, these explosions will all be alot larger than just driving around on the highway, and since your sealing isn't increasing (piston ring to chamber wall), more blowby will occur. These combustion gasses that are "blowing by" into the crankcase have carbon and oil, un catalyzed noxoius gasses, etc. This causes an increase in air pressure in the crankcase which can cause alot of problems (most obviously it would be harder for the pistons to travel). This is a bigger issue in forced induction motors btw. They get mixed in with the oil, and it's a whole big mess (coincidentally, carbon from blowby is one of the big reasons your oil turns black). So these gasses are vented back up into the intake tract so they can taken back into the combustion chamber and properly combusted, catalyzed, maintain correct pressure in the crankcase, etc. Venting them straight back to the intake does a few things that are bad though 1: you're introducing nasty low oxygen content combusted fumes back into your nice cool oxygen rich intake charge 2: you're bringing dirty carbon and oil filled soot back into the intake tract 3. sensors or equipment installed (manifold pressure sensors, etc) can be distrupted or suffer premature wear. This is where catch cans come in, they are designed to help pull the oil part of the nasty venting out, and keep the air intake clean. They also make air/oil seperators, and lots of people make them themselves and put in more filtration to make the air even cleaner.
Here's a pic of a catch can at work:
As you can see, the air coming up from the crankcase is dark and sooty, but this guy installed a catch can (filled with stainless steel wool) and as the air comes out to the intake, its no longer filled with soot.
That's the general idea behind what the catch can does (as I've come to understand it).
Now, why do I think it's not really useful in a rotary motor?
Well where do blowby gasses go in the rotor housings? They don't go shooting straight down into the oil pan that's for sure. They most often go to the other sides of the rotor. The oil gets contaminated with soot and other particulate matter, but the air factor really isn't involved in a place where it can be vented. And by the time the oil leaves the combustion chamber and is in a place where it could be vented back to the intake tract, it's not really an issue to worry about beyond what the factory has already done. The soot thing is an issue, but unless you're running a can that's going to actively pull the soot out (like this guy did, he cut the can in half and stuck in SS wool to attract the oil and soot to, then routed the inlet pipe into the can down to the bottom so it would come up though the wool and exit at the top), you're not going to stop much with a regular catch can as they are usually just hollow inside though some have more elaborate filtration...
Where you got the notion that particulate matter was a lubricant I can't even begin to guess... Anyways, the engineers didn't intend for oil to act as a lubricant in the intake system, that's crap. Motors are designed for all driving conditions and if someone baby's the car for 100k miles, runs MMO and synthetic oil (which would minimize blowby even more), they won't get much blowby at all (piston engine we're talking here). Does this mean that their TB's wont be "lubricated" correctly? Nope.
And as far as atmospheric venting causing power losses... once again I don't know where you got this idea. What would be the point in an engine designed for absolute power, that's going to be rebuilt after less than 250 hours of running, to have dirty oil contaminated air taking up space in your precious intake charge? You're just trying to keep the crankcase pressure down, so put it into the atmosphere. Ever wonder what these were for on a motor?
http://store.summitracing.com/partde...5&autoview=sku
Perhaps the stock ECU of a modern road car might have trouble coping with the vacuum changes, but like I said, it's for racing so you should be on a standalone ecu. It makes the car smell of oil and that doesn't go over well with the ladies.
Now that I've ranted and typed for 2 hours at my work, I need a cookie.
sure, with the way you have your oil catch can routed, its nothing fancy but "a break in the line" where a "can" can be used to catch perhaps an overflow of oil for whatever reason it is that it overflow from the crankcase( but obvious there are cases in threads around here about overfill oil going into the intake, BEFORE the revised oil tubes in newer models) maybe useful for motor oil thats over-filled.
but,
-one module exercise was to check PCV operation. which was to pull pcv valve out and check for proper spring play under vacuum, which will create a clicking sound when u put your finger over the opening.
why would you even recommend anyone to use this in their modern cars?
even hot rod shows with motor swaps have a recommendation to fabricate the old style type valve covers to run PCV instead of without.
summit racing only sells products, but they don't need to educate every consumer of its proper use.
so please don't tell me you have ceramic headers and ALSO have it heatwrapped!!!
but, MAYBE YOU"RE RIGHT. if you don't know where i get my ideas, and maybe that it somehow doesn't make sense on one make of cars on others... i can just as well be wrong. but starting off with info from an valid automaker's training background does help me in not making the same mistakes again.... especially in the installation of a ricer breather filter thats of no use on a honda valve cover.
like i said, i was once an idiot too. how anyone here takes my opinion is up to them. if they are smarter or more trained, go right ahead and enlighten me.
05-02-2008, 01:47 PM
#19
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I thought they did? Not picking on you or anything, but here are some weak examples.
http://www.streetunit.com/GReddy_Oil...p/12003510.htm
http://www.optionimports.com/oilcatchcan.html
Quickiest I could find using at 2 second search.
Anyway...............I learn sumtin on here everday........even in the lounge!
http://www.streetunit.com/GReddy_Oil...p/12003510.htm
http://www.optionimports.com/oilcatchcan.html
Quickiest I could find using at 2 second search.
Anyway...............I learn sumtin on here everday........even in the lounge!
That was sarcasm I used. I know it's called a catch can. You don't seem to realize the way you come off over the internet though, like when I asked about rough idle and you told me to check if the clamps of the intake hose were tight... Sounds like you're talking down to me telling me such blatantly obvious things. I wrote up paragraphs of information on the catch can and it's function... of course I know what it's called.
Maybe you're just being sarcastic too but it doesn't seem like it...
TrochoidMagic, that's not my catch can, I found a DIY VW guy. I know this PCV test you're talking about, but, like I said venting to the atmosphere is for racing engines. All that emissions control cr*p would be gotten rid of or heavily modified. Alot of guys try to imagine daily drivers as "racing" engines, but that's just ego stroking.
Daily Driver Engine:
Racing Engine:
Edit:
so please don't tell me you have ceramic headers and ALSO have it heatwrapped!!!
but, MAYBE YOU"RE RIGHT. if you don't know where i get my ideas, and maybe that it somehow doesn't make sense on one make of cars on others... i can just as well be wrong. but starting off with info from an valid automaker's training background does help me in not making the same mistakes again.... especially in the installation of a ricer breather filter thats of no use on a honda valve cover.
like i said, i was once an idiot too. how anyone here takes my opinion is up to them. if they are smarter or more trained, go right ahead and enlighten me.
but, MAYBE YOU"RE RIGHT. if you don't know where i get my ideas, and maybe that it somehow doesn't make sense on one make of cars on others... i can just as well be wrong. but starting off with info from an valid automaker's training background does help me in not making the same mistakes again.... especially in the installation of a ricer breather filter thats of no use on a honda valve cover.
like i said, i was once an idiot too. how anyone here takes my opinion is up to them. if they are smarter or more trained, go right ahead and enlighten me.
Anyways, I'm done with this thread. Buy what you want, but unless you're running a forced induction piston motor, it's really not gonna do much good.
Last edited by BMonkey; 05-02-2008 at 03:02 PM.
05-02-2008, 04:04 PM
#20
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Don't mind me............I'm just grumpy. Broke my heel about three weeks ago, have non-walking cast, and haven't driven my 8(but very sparingly in that time period) as doctor ordered me not to do so.
I'm abandoning this thread as well.
I'm abandoning this thread as well.
05-03-2008, 02:58 AM
#21
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wait ...i thought IT IS called an Oil can catch ...didnt i put it in the title ?
and after 20 posts , i still cant get an answer to my question ....what does this thing do ? it comes together in the box >.<
oh yea...the blue thing its sitting on is my jeans ...i took a quick pic of it while resting it on my knee ...if anyone was curious :P
and after 20 posts , i still cant get an answer to my question ....what does this thing do ? it comes together in the box >.<
oh yea...the blue thing its sitting on is my jeans ...i took a quick pic of it while resting it on my knee ...if anyone was curious :P
Last edited by luv4eternity; 05-03-2008 at 03:04 AM.
05-03-2008, 10:35 AM
#22
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Sorry, I can't help. It looks like some sort of plug for something?????? But I can't imagine where it would go. Will it fit anywhere on the can itself? I'm not saying to do this, but if you were to pull out on of the two plastic hose connections.......would it plug that hole? I would do a google serach for Greddy Oil cans and see if you can find out what it is.
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