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Discussion Starter #1 (Edited)
My dad had a air/oil seperator installeld in his pick-up and his caddy. Its run inlune in the PCV line that runs to the throttle body. There is a "filter bowl" that collects the oil that. It seems that they make more power now, and they swear that that your engine burns cleaner and will last longer. Has anyone else herad of this before. I'll try to find the name of the company, and a web site too.
 
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I had one in a turbocharged car and was amazed at what it caught. I used a fule filter housing that you could replace the element in. I did not use the filter though. Cheaper than buying a real catch can. about 4 bucks at your local Autozone, schlep boys
 

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I run a catch can.
I don't run a turbo, but all the turbo guys run one. They have found that at boost, even the slightest mist can cause detonation, and they all know that the PCV WILL let mist past it, boost, or no boost.
I ran a line from the PCV to the can, then from the can to the base of a 1" spacer. Just after the catch can I plumbed in a large gas filter before that line goes back to the base plate. It also catches any excess mist that the can misses.
The can after a week of very hard runs 300 miles, gets about an ounce of oil in it. You can see oil in the filter as well.
If I drive at normal speeds rev's under 5,000, there is no oil accumulation. If however, I am hitting my rev limiter 6,600 a lot, which I do, then I get oil in the can.
I don't know if there is a measurable difference, as I have not tested it on the rear wheel dyno.
One thing is certain, without the can, that oil was ingested into the engine, which will decrease power, and could cause detonation.
 
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We didnt run the catch can for detonation, 68SSGrandpa, we ran it because our cars would vent the pvc into the intake before the turbocharger and we didnt want oil on the compressor. Detonation was the result of too much boost and not enough timing, resulting is a severe dieseling issue, then a piston and con rod saying goodbye to the crank. When I first saw the pictures of Novaboys pistons......my first though was "Wow, How much boost was he running!"
 
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Many people don't reailze that oil mixing with inlet fuels LOWERS the overall octane of the fuel.

People that have run/raced premix/oil injected two stroke engines know this all too well.
 

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When you phyically see the oil/water that a crankcase evac system takes out its amazing. Mine is not a Vac system, but a simple catch the crap system.
I read the entire article on that " Condensor" device. One thing that caught my attention was that the condensor will remove oil and water vapor, which looks white when collected.

The PCV system was invented to recirculate ( burn) the polution/stink/water and oil vapour that developes in your crankcase.
Made sence to me, that I really didn't want to burn that crap to save the environment, maybe I could find a better way. Would you want to dump that stuff direct into your gas tank? You might as well, cause you are burning it anyway. What does it cost in HP to burn a bit of oil and water vapour?
Normally the PCV is hooked direct to the intake system, so I just put a catch can, and an oversize gas filter in its path before returning to the intake. Now my engine still sucks crankcase air, but its free of oil mist / water, and unburnt hydrocarbons.
The oversize gas filter at 500 miles looks like a jar of Mayo has been spit into it. The catch can if I street beat 6,600 rev limiter for all 500 miles has about 6 oz of oil in it.

Yahoo, I have saved the environment again, and in the process generated a lot, not just a few extra HP.

I have not rear wheel dyno'ed the gain, but it is a noticable gain.
 

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Shawn63,
I have about 10 pics of it, but currently do not have a host site for them.
I did an initial test hooking from the PCV direct to the carb base with just the filter in between, no catch can. That test and picture shows about 1 oz+ of oil in the bottom of the filter, and the filter 100% soaked in oil from the mist. That test was a brand new filter, and 50 miles of street driving with some serious hard throttle runs.
I did one more test with a new filter plumbed without the can again, this time driving normal, without super hard throttle. On that test, the filter got soaking wet, but no large accumulation in the bottom of the filter.

It was after seeing the accumulation of oil from hard runs, I plumbed a catch can as well.
By the way, my oil between changes is now pristine clean. Before that, with all the recycling of gasses/mist, my engine was doing, the oil would be dark at 750 miles.

Just to let you know, my engine has no exessive blowby. In fact, we have very strict smog rules here, and yearly have to run an aircare test on a rear wheel dyno to get insurance. I have aircared this engine for 3 years, prior to the can system, and this year with the can system it aircared like a Honda, see my cam spec below, also we have a 950HPXE Holley .

Lethal, a PCV has a check valve built in, so the worst you can do is blow a line off the catch can, but it would never back up past the PCV valve.
 

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Discussion Starter #12
This is the filter housing I was going to use as a catch can

I think that it would work just as good. only $27.95 from summit
 

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This is very interesting. I've used catch cans before on race cars but the stainless mesh used in both units to separate oil from the air is a novel idea. The more expensive unit also has silicate gel for water absorbtion.
Their claims of 15% mpg increase is intriguing. Anything worth 2mpg is worth investigating.
 

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Discussion Starter #14
Mom says that her caddy gets better milage but dads truck gets worse, but that is because he cant keep his foot out of it, old men and thier toys:D
 

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Shawn63
I have placed a few pic in photobucket.
The one up near the valve cover was the test, filter from the PCV direct to the carb base. I gathered about an ounce of oil in one street run. The rest of the pictures are not to great for placement of the can, but I put the can by the rad.
http://photobucket.com/albums/e200/Nova68SS/
Hope this link works, I have not used photo bucket before.
 

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Link works fine; thanks. Is there anything inside your catch can such as mesh? Is it purpose built for pcv use or was designed for something else?
 

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Shawn,
Purpose built as catch can for in line with a PCV, made by Greddy.If you do an internet search on Oil Catch Cans, you will come up with a few. I belive I studdied about 7 or 8 different ones, and settled on this one. Mainly because it has a sight tube to see oil accumulation.
No screen inside, but the inlet tube goes down 1/2 to the bottom, and the outlet vac side tube is near the top of the can. That way, when the can starts to fill, hopefully never, the top suction side is not submurged in oil. If you look close there is a sight tube running the length of the can. As it collects oil the oil raises up that sight tube, so you can see how full it is. The tube also has a bung at the bottom for draining the can.
I would not trust stainless mesh, because I have seen how milky, like I said as thich as Mayo that the oil/water/vapour sludge gets. I would think especially in cold weather, it would get thicker than 190wt grease, and just plug that screen.

I don't think you can see my entire set-up in those photo's. My PCV line runs to that can under my inner fendor and attaches to the can, mounted by the Rad. From the can, the out line goes to the filter, then through my inner fendor toward the back of the motor, and then attaches to a 1" open spacer I have under my carb.
By running the lines behind my inner fendor, they are all hidden. All you see is the catch can by the rad on the passengers side. The window washer container hides the filter.
 

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After finding some oil build up in the intercooler on my Subaru, I installed an inline universal fuel filter that I picked up from Napa. It worked quite well but you have to keep an eye on it, or at least the small one I got, to make sure it stays clean. I ended up getting a generic stainless steel catch can on ebay and it worked like a charm. It was around $30 IIRC.
 

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The nut that I am, I have been kickin around the idea of making one for a while particulary for my supercharged firebird. Well this thread got me off my butt. I did not want to pay $169 for that fancy can that I posted before so I decided to make one. Mine is made from copper dwv pipe 1.5 inch in diameter and standard copper pipe fittings.

In my design the "dirty" vapor enters thru the top side. Then the air must travel down and up a center pipe. The pipe at the bottom has points on it to help cause the oil to drip down and inside of the pipe there is a brass plate with holes in it to also help reain the oil. At the top of the pipe/can assembly I am putting in a stainess fuel filter screen (I'm going to see how this works out-dont want it plugging up- also don't drive it in cold weater).

I'll post pics of my progress should cost about $25 buck when done.

I did not want a large catch can this will be about 6" long when done and 1.5" in diameter.
 

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Ok here is what I put together.

The parts:

6" of 1.5 DWV copper pipe
2 1.5 caps (one end cap drilled hole to size of brass collar of union)
1 3/4 union (turned brass hex down on lathe to make circular)
1 1.5" of 3/5 pipe used on bottom of union to join coupler and hold brass disk with holes
1 3/4 coupler with points cut on bottom end
1 piece of brass with 1/8 holes cut to into circle to use as a condenser to help stop oil bypass
1 brass reducer which I turned down to fit in top of union and join brass elbow to top

2 brass elbows
1 3.8 hose barbs
1 petcock



Here is what the center baffle looks like:



Almost finished catch can (still need to attach mounting brackets) and paint:
 
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