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Old 01-10-2011, 12:39 PM   #21
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In for melted home depot hoses.
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Old 01-10-2011, 05:35 PM   #22
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I am having essentially the same issue as you with more or less the same setup. I'm very interested to see how this works out for you, keep the updates coming.
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Old 01-10-2011, 06:20 PM   #23
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In for melted home depot hoses.
Nah, it will get brittle and break in two like mine did
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Old 01-10-2011, 06:42 PM   #24
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In for melted home depot hoses.
Hustloid what size fittings did you use? Also how much did you pay for the bung welding?

I need to get this done asap but the sad part is my nice black powdercoated valve cover will be ruined :****:
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Old 01-10-2011, 06:46 PM   #25
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Has anyone compared the protege cover to the mazda cover? One of the ports is relocated to the rear. I'm collecting a little in my catch can, but it's only street driving.
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Old 01-10-2011, 07:12 PM   #26
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I have a protege cover that I removed the plates from. Its hanging on my garage wall (contemporary art lol..) need pics?
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Old 01-10-2011, 08:16 PM   #27
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Just wondering if the design is better .
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Old 01-10-2011, 09:02 PM   #28
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I have one from a ford escort I could post pics of also but I think it would be worse with the port on the side of the head which would become the back of the head in/on a miata.
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Old 01-10-2011, 09:40 PM   #29
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I have one from a ford escort I could post pics of also but I think it would be worse with the port on the side of the head which would become the back of the head in/on a miata.
maybe it's the escort one I have.

rectangle valve cover, doesn't cover cam sprockets, with ports on passenger side (facing fender and firewall).

I though maybe the covered baffling inside the cover may be different and inhibit excessive blowby.
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Old 01-23-2011, 01:09 AM   #30
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Jason, any updates? I am considering plugging both of the factory ports and drilling through the top of the valve cover on both sides in order to get the breather ports up as high as possible (and away from liquid oil).
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Old 01-23-2011, 02:36 AM   #31
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where did you get the scrcrubbers?
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Old 01-23-2011, 12:36 PM   #32
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where did you get the scrcrubbers?
I'd start checking your local supermarkets. his look to be fairly lightweight and porous. and definitely not impregnated with weird chemicals for scrubbing.
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Old 01-23-2011, 01:59 PM   #33
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High pressure carries oil better than low pressure. Adding scrubbing material lowers the volume, therefore increases pressure (main reason why Julian's first try with lots of scrubbing material ended badly). In my opinion scrubbers is a temporary thing that works good in the beginning, then bites you in the behind once it gets soiled as then it helps carry the oil. From what i can find, the only reason people choose not to use a catch can is that they have to empty it. Why not add a bottom to top fed catchcan so the oil can drain back after the motor is turned off?
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Old 01-23-2011, 03:34 PM   #34
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Sav, if you do that you have to add your own baffling, e.g. use the "real" oil catch can linked to in the other thread with bbundy's pics. I think it's better to modify the factory baffling.

I haven't driven the car in weeks, I've been doing a lot of little odds and ends while waiting for the weather to turn nice (which it just did).
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Old 01-23-2011, 03:35 PM   #35
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High pressure carries oil better than low pressure.
This statement makes no sense. Do you mean the higher *density* allows it to carry more oil? Even so, the increased pressure might be only 1% .(0.15 psi out of 15 psi)
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Old 01-24-2011, 01:38 AM   #36
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This statement makes no sense. Do you mean the higher *density* allows it to carry more oil? Even so, the increased pressure might be only 1% .(0.15 psi out of 15 psi)
When you decrease the volume but you keep the same flow, more oil will be carried away with the direction of the air flow.
Let me try to explain it with an example.
You put a 5 foot diameter fan at the end of a wet tunnel. Hardly any water will move. Now you take the tunnel and fill one side of it with bricks so now the tunnel is only let say 3 feet across. You can see that same fan in the beginning will start moving air across at a higher velocity and it will now push the water around.

The velocity and pressure increases in the 2nd case. More of the water moves.
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Old 01-24-2011, 04:28 AM   #37
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Quote:
Originally Posted by JasonC SBB View Post
Sav, if you do that you have to add your own baffling, e.g. use the "real" oil catch can linked to in the other thread with bbundy's pics. I think it's better to modify the factory baffling.

I haven't driven the car in weeks, I've been doing a lot of little odds and ends while waiting for the weather to turn nice (which it just did).
I'm going to drill into the factory baffle chambers, but instead of having them on the sides ala factory (and very close to the floor of the baffles, where I'm sure liquid oil sits and pools) I'll put them on the ceiling of the chamber, which will hopefully promote less liquid flow (and thus more airflow). I don't care as much about the aesthetics of such a change as others might.

I don't want to return the blowby waste to the sump - I know what it looks like and I don't want it anywhere near my bearings/turbo.

triple88a, the scrubbers work by giving the oil vapor lots and lots of surface area to pass over, which turns the vapor into liquid oil and stops it from being carried into the vent tubes.
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Old 01-24-2011, 04:42 AM   #38
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Quote:
Originally Posted by Savington View Post
I'm going to drill into the factory baffle chambers, but instead of having them on the sides ala factory (and very close to the floor of the baffles, where I'm sure liquid oil sits and pools) I'll put them on the ceiling of the chamber, which will hopefully promote less liquid flow (and thus more airflow). I don't care as much about the aesthetics of such a change as others might.

I don't want to return the blowby waste to the sump - I know what it looks like and I don't want it anywhere near my bearings/turbo.

triple88a, the scrubbers work by giving the oil vapor lots and lots of surface area to pass over, which turns the vapor into liquid oil and stops it from being carried into the vent tubes.


Are you going to drill into both intake and exhaust side? I am thinking about just doing the exhaust side and porting out that middle-exhaust baffle connecting hole. The exhaust side baffle is so much more extensive and it's um, better baffled.
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Old 01-24-2011, 03:58 PM   #39
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Quote:
Originally Posted by triple88a View Post
When you decrease the volume but you keep the same flow, more oil will be carried away with the direction of the air flow.
Let me try to explain it with an example.
You put a 5 foot diameter fan at the end of a wet tunnel. Hardly any water will move. Now you take the tunnel and fill one side of it with bricks so now the tunnel is only let say 3 feet across. You can see that same fan in the beginning will start moving air across at a higher velocity and it will now push the water around.

The velocity and pressure increases in the 2nd case. More of the water moves.
Agreed on the velocity increase, but the pressure increase is mild and doesn't affect the results. Besides the absolute pressure in my crankcase is lower now despite the scrubbers, because most of the pressure drop was across the tiny hole which I enlarged.

Yes the velocity is increased by the scrubbers, but the scrubbers present a lot of surface area to "catch" the oil vapor. That's the theory anyway.

But if the scrubbers do make things worse instead of better, a better scheme would be baffles that cause the oil to zig zag, so when the gas zigs, the oil doesn't and hits the wall and drains down. Or use a BMW style separator, which makes the gas flow in an ever decreasing spiral (they call it a "cyclone separator).
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Old 01-30-2011, 08:27 PM   #40
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Although the color variety of those scrubbers is absolutely fantastic...

What about trying some fuel cell foam (http://www.summitracing.com/parts/SUM-290190/?rtype=10) instead? It seems like that foam would catch the oil better. I would use it only in the beginning of the baffle because it seems like the fuel cell foam would be worse in regards to the "velocity argument " where it could assist the oil in reaching the breather port.

I'm almost positive the fuel cell foam is polyurethane foam with a maximum temperature of 150-250F which may be a bit low for this application. McMaster has polyimide foam that's rated for 400F but they only sell 24"x48" sheets where 1/4" thickness costs $45; 1/2" for $80; 1" for $125; 2" for $210.
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