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Hi All,

I have searched and read numerous threads regards oil catch cans and am looking for a bit of direction. Most seem to acknowledge that the standard (cheapie) catch cans are nothing more than a can (no internals) and need to be stuffed with a filter (steel wool / scourers etc) in order to actually do what they are supposed to do - seperate oil from air and catch the oil. There are a couple of catch cans (more expensive- such as the Essential and ARC cans) which replace the washer bottle (GTR's only I think) and apparently do all they are supposed to do. These cost around $400-$500, which isn't exactly cheap. I have also seen the air/oil seperators (cylinder type) which fit across the top of the engine (GTR). From what I've been told, you also need a catch can with these to collect the oil. This type of air/oil seprator and cheap catch can would work out to be much cheaper than the expensive unit "which does it all". Question are-

Is this setup better or worse than the expensive catch cans?

Do the expensive ones do everything they claim to?

Apart from reducing octane rating and performance, does oil blow back damage anything?

Thanks for your help.

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Hi All,

I have searched and read numerous threads regards oil catch cans and am looking for a bit of direction. Most seem to acknowledge that the standard (cheapie) catch cans are nothing more than a can (no internals) and need to be stuffed with a filter (steel wool / scourers etc) in order to actually do what they are supposed to do - seperate oil from air and catch the oil. There are a couple of catch cans (more expensive- such as the Essential and ARC cans) which replace the washer bottle (GTR's only I think) and apparently do all they are supposed to do. These cost around $400-$500, which isn't exactly cheap. I have also seen the air/oil seperators (cylinder type) which fit across the top of the engine (GTR). From what I've been told, you also need a catch can with these to collect the oil. This type of air/oil seprator and cheap catch can would work out to be much cheaper than the expensive unit "which does it all". Question are-

Is this setup better or worse than the expensive catch cans?  

Do the expensive ones do everything they claim to?

Apart from reducing octane rating and performance, does oil blow back damage anything?

Thanks for your help.

I have treid the "expensive, do it all style" and guess what, they are simply "expensive", they don't do it all. The concept of a catch can is to slow the movement of the air down so that the oil has time to fall out of susppension and collect in the bottom of the can. So a bigger can is better than a smaller can due to its ability (space) to slow the air flow down. Some of the larger cans have a number of simple baffles so the airflow has to bend, this also helps the oil to fall out of suspension.

Personally, I have found the cheaper catch cans filled with stainless steel wool to be totally satisfactory. The wool acts as a filter as it makes the airflow bend a lot more than the simple baffles. Spend $90 on the catch can and $5 on a pack of stainless steel wool and spend the saved $300 on something that actually makes the car go faster.

:(

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Thanks SK,

but tell me - is the oil blow back ( and I'm talking about track work here) damaging or just a pain in the arse. For the sake of a miniscule improvement to the RON rating of the fuel, are they actually worth putting in?

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Thanks SK,

but tell me - is the oil blow back ( and I'm talking about track work here) damaging or just a pain in the arse. For the sake of a miniscule improvement to the RON rating of the fuel, are they actually worth putting in?

A few things to note first;

The blow by goes directly into the engine via the PCV valve when the engine is not under boost. This means you get quite "raw" oily air into the combustion process, but it's not under boost so it doesn't really affect performance. But it does foul up those cold heat range plugs and gunk up the exhaust, depending on how much is actually combusted.

The blow by goes indirectly into the engine via the inlet (between the AFM and the turbo) when the engine is under boost. This means you get quite oily air hittting the spinning compressor, in the intercooler piping and into the intercooler. This is the worst part for me, remember the catch can concept of slowing the airflow and bending it to get the oil out of suspension. As such, the intercooler makes a great catch can, plenty of space and lots of bending. So you end up with an intercooler coated with oil on the inside, and oil is a OK insulator. That means your intercooler no longer functions as efficiently (ie; hottter air).

Then you still get some oily air into the combustion process, hotter air plus lower RON = even more chance of pre-ignition and lower power.

Hope that makes sense:cheers:

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Talk to Nigel at Ice Performance, they make a custom Washer Bottle/Catch Can unit that looked awesome.

Cheers

Pete

Leewah has one on his GTR

Are you sure they are ice's? Sounds a lot like Racepaces, maybe they resell Bens?

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is it best to completely pack the can with steel wool? or jus place a small amount in there near where the oil enters the catch can?

Fill 'er up:cheers:

PS; I usually stick the stainless steel wool into an old stocking, it makes getting them out easier and stops any small bits of stainless from floating around.

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why hasnt anyone made a cheap ass screw top catch can yet??  theres plenty of cheap sealed hollow ones out but none that can be opened. im tempted to just make one out of pvc piping with a screw top lid..LOL

This is the style I use, just take the filter off the top and fill 'er up. The hole looks small in the photo but is big enough to fit a stocking in and then, one by one, poke in the stainless steel wool. I don't usually remove it, I simply fill it up with 50/50 kero and metho, slosh around and rince with water.

show071.jpg

You can get them with 2 inlets at the top and I have even seen one with a tap on the bottom for draining.:D

For those with bling inclinations you can get them anodised like this fuel swirl pot;

show058.jpg

PS; Thanks to Mick for the photos

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Are you sure they are ice's? Sounds a lot like Racepaces, maybe they resell Bens?

I do believe he has them fabricated externally.

could be wrong :D

but they are sexy as. Im getting one. Gets rid of the ugle washer bottle :D

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why hasnt anyone made a cheap ass screw top catch can yet??  theres plenty of cheap sealed hollow ones out but none that can be opened. im tempted to just make one out of pvc piping with a screw top lid..LOL

MONZA make them cheap(and shiney). I bought a square power steer can and modified it to be a 100% plumb back catch can it has a removable top, total fitted cost with DIY mods is $102.95, so I now have a budget can which has a drain bung with tap under the car and a removeable top and baffled with s/steel wool stuffed in a stocking which can be replaced by removing 4 hex head bolts....easy as drainage and maintenance.

I'll post pics when I get the film on CD and maybe a DIY using monza p/s can. :D

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