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I was looking on Ebay today and saw quite a few auctions for Oil Reservoir Catch Tanks for the Z. Can someone explain if this is really something needed and if so, what in simple terms does this do? :helpsmilie:
 

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[/quote]
Originally posted by jcn30127 on another forum...

Not all exhaust exits out the exhaust valves into the exhaust manifold, and out the tail pipe.

A small amount leaks past the piston rings and into the crankcase or oil pan.

In the late 1960's/early 1970's, engineers discovered that they could run a vacuum line from the intake manifold to the crankcase and suck these "blow-by" gases back into the engine and re-burn them in the combustion process. They also learned that by placing a negative pressure on the crankcase, that the engine ran more efficiently and cleaner.

On FI engines the blow-by gases (unfortunately) tend to be higher. The OIL CATCH CAN is placed mid-stream in the vacuum line to catch any large or heavy blow-by ingredients before they reach the intake manifold. If the blow-by gases have a unusually large amount of oil in them, it CAN reduce combustion efficiency. The catch can reduces this possibility.

Ideally, piston rings would seal perfectly and their would not be any blow-by. Conversely, too much blow-by is an indication that the piston rings are not sealing properly, resulting in lower compression and power levels.
 

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I'll make an attempt to explain. All engines need to vent their crank cases as a small amount of the intake seeps buy the piston rings. Old cars just dumped this to the ground with a "Road Draft Tube". With emissions in the late '60's, this blow-by was drawn back into the intake manifold through a PCV valve, effectively burning the unburned carbon and the fine mist of oil in the gases. Our Z's are no different.

BUT, some of the oil in the crank case gas separates, and forms a sludge in our lower plenums. The oil catch cans separate the oil form the gases, keeping the plenum cleaner. A drawback is that the catch can needs to be emptied every once in a while.

Class dismissed! :cheers:
 

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Discussion Starter #4
The big question is...........is it worth buying, or should I wait until the Z has more miles on it before installing such an item due to wear and such in the engine thereby having more "blow-by"?
 

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The biggest advantage to an oil catch can is that shiny aluminum in your engine bay. Do you need anything performance-wise first?...I'd do intake/exh., stuff like that 1st....
 

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Yeh...if you're gonna dog it. Like I said, it wouldn't be the 1st mod on my list, but they do look nice in the engine bay & serve a purpose, as well.
 

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Im having to empty mine after every track event and I am NA. Its black Oil, but my oil pressure and oil level look normal. What should I do?
Any help would be appreciated! Thanks!

quote name='lionkiller' date='Mar 29 2005, 11:40 AM' post='86484']
Yeh...if you're gonna dog it. Like I said, it wouldn't be the 1st mod on my list, but they do look nice in the engine bay & serve a purpose, as well.
[/quote]
 

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Great thread guys, keep it going! I've been looking into these lately too.

What is the difference between catch tanks on the market? I know of Greddy, ARC, and tons of universal ones that even have baffles in them. Which is the best option? Do they catch differently? Where do they connect at?
 

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The baffles are usually there to slow down the flow of air through the catch can, which means there's more time for the heavier oil to "drop" out of the air. You also get some with filtered breathers on the top, but I have no idea what those things do since you want that air to be vented back into your intake.


If you are looking for a catch can, my advice is to find one with a valve at the bottom and designed in such a way that you can reach it easily with a small bottle. Having to empty your catch can by pulling the entire thing out is a pain in the backside, so its better to just have a tap you can stick something under to drain it with.
 

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A catch can is a good functional part on even a bone stock car. I have a home made catch can that I made from an air compressor water seperator. On my Tiburon, I used to have to empty it once every couple of months. On the Z, I empty it every 2 to 3 weeks. The Z's crankcase ventilation system blows out alot of oil. When I replaced my plenum with only 4,000 miles on the car, the inside of the plenum was covered in oil.
 

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OK....I think we all get the technical merit of the can and the sexy look that can be sported.....but like buddy said, what is the difference from the big name brands and the ones on ebay?
 

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OK....I think we all get the technical merit of the can and the sexy look that can be sported.....but like buddy said, what is the difference from the big name brands and the ones on ebay?
Probably the quality of the finish and the welds. I'm more of a "function over form" tuner, so I made my own from Lowes parts for about $15.
 

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On the Z, I empty it every 2 to 3 weeks. The Z's crankcase ventilation system blows out alot of oil. When I replaced my plenum with only 4,000 miles on the car, the inside of the plenum was covered in oil.
Seriously? I changed my plenum out at around 17k and had a pretty clean one.

We need pics of that can you made.

Probably the quality of the finish and the welds. I'm more of a "function over form" tuner, so I made my own from Lowes parts for about $15.
Sounds like a good DIY. Do you have any step by step instructions you'd like to share?
 

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I'll post up some pics tomorrow as well as a parts list.
 

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Some local guys were selling these for about $80. I didn't jump in on it because I was thinking I would go with one that fits in the engine bay better, but this looks like a good design. Where does the catch tank hook up to?


 

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Ahhh I got a pic of the hose and saw where to connect both hoses too. So I assume you hook one hose to the one end and the other at the other end. So the can is technically between the to ports that was ORIGINALLY connected by one hose. As illustrated on the pic.
 

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