Oil Separator
- Thread starter cobra498
- Start date
fjpikul
GT Owner
BlackICE
GT Owner
New Information
All the talk about oil separators made me curious to how the PCV works on the FGT given that it is a forced induction motor.
Assuming my PCV is not broken.
My PCV flows air in both directions without a check valve to prevent manifold boost from reversing the normal flow. That means that under boost, the driver's side valve cover WILL be spewing oil vapors into the front of the throttle body, even if your engine had zero blow by! To really eliminate oil from going into the intake would require TWO catch cans.
As far as line size is concerned, on the passenger side the line could be 3/8 or less, since the PCV limits flow to a small amount. On the drivers side I would use a line size at least as great as OEM to ensure that crankcase pressure is vented.
All the talk about oil separators made me curious to how the PCV works on the FGT given that it is a forced induction motor.
Assuming my PCV is not broken.
My PCV flows air in both directions without a check valve to prevent manifold boost from reversing the normal flow. That means that under boost, the driver's side valve cover WILL be spewing oil vapors into the front of the throttle body, even if your engine had zero blow by! To really eliminate oil from going into the intake would require TWO catch cans.
As far as line size is concerned, on the passenger side the line could be 3/8 or less, since the PCV limits flow to a small amount. On the drivers side I would use a line size at least as great as OEM to ensure that crankcase pressure is vented.
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STORMCAT
GT
I have never found any traces of oil on the front of throttle body, This has been discussed before years ago, Check with Shadowman he can give you the scope on the drivers side crank ventilation..
eg1985
GT Owner
That is theoretically correct; however, the OE baffle in the valve cover coupled with the elbow and the hose size (keeping pressure down) in the drivers side hose do an excellent job of keeping oil vapor out of the inlet side of the throttle body. I have yet to see a throttle body on a GT with an oil residue on the air filter side. On the LSx engines, that is a huge problem however, and two oil separators or a catch can are the only way to go on those engines.
eg1985
GT Owner
Agreed. You run a huge risk of blowing an engine seal out if you put a check valve in the "clean" side hose. That hose should remain open.
MoTeC Magic
Spectator
Morning Guys,
This is what we did on Mark’s (FUBAR) car.
http://www.fordgtforum.com/forums/s...ystem-(lots-of-pix-not-dialup-friendly)/page3
Page 3 and 4 I believe have the images of the breather system I developed. Because of the large fittings and hoses, the blow by air velocity is much lower than when using the stock breathers, because of this it carries much less oil and therefore not much makes it to the actual breather canister other than air and some water vapor. Other benefit is that it relieves more crank case pressure for the higher horsepower vehicles.
The tank can be mounted other areas in the car if desired. They’re also available in anodized, what ever color you desire, hard black for instance.
Cheers
nz05gt
GT Owner
BlackICE
GT Owner
You are right, I was WRONG and stand corrected.
I spoke with Shadowman today and he pointed out that the hose from the PCV goes to the intake side of the blower and not to the intake manifold as in most cars. So air is always being sucked through the PCV, even during boost. The only time the driver's side would vent oily air is if the blow by gases exceeded the flow rate of the PCV.
I have never met a person more knowledgeable on cars than Shadowman! Are am sure they exist, but none spend the time to explain and help while expecting nothing more in return but a thank you. Indeed a rarity in today's world! :thumbsup
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MoTeC Magic
Spectator
Hi Guys,
I think this is really simple... most of the GTs that are modified are making pretty good power (900-1000hp at the crank). They are either supercharged or blower mods, or both. The two section oil scavenge pump can't keep up with the blow by (air pushed past the rings on compression and the power stroke when the motor is under boost). This excess air builds up in the crankcase as a positive pressure. The negative pressures (sucking) that are before the compressor (especially on a blower car), help the positive pressures in the block push oil through the stock PVC breather ports. These PVC breather ports, because of emissions laws, are routed back into the intake since the air they emit contain oil.
Oil, through our intake tract, is bad for our motors to consume. The oil fouls our plugs and o2 sensors... worse yet Oil has a lower flash point than gasoline... because of this, sucking oil into the intake or into the combustion chamber, can and does often lead to detonation under power. Detonation destroys engines.
Best advice I can provide and those that have done similar mods can provide, is to remove your PVCs and vent them into a separate catch tank that doesn't connect to your intake tract.
I personally recommend larger lines -12 at the absolute min and preferably -16 lines. The reason being that the smaller the hose, the higher the airflow through them and the more oil the air will carry... verse a large line with much lower air velocity and therefore much less likely to carry oil out of the motor.
A few examples of the pieces I built for Mark’s GT
Cheers
I think this is really simple... most of the GTs that are modified are making pretty good power (900-1000hp at the crank). They are either supercharged or blower mods, or both. The two section oil scavenge pump can't keep up with the blow by (air pushed past the rings on compression and the power stroke when the motor is under boost). This excess air builds up in the crankcase as a positive pressure. The negative pressures (sucking) that are before the compressor (especially on a blower car), help the positive pressures in the block push oil through the stock PVC breather ports. These PVC breather ports, because of emissions laws, are routed back into the intake since the air they emit contain oil.
Oil, through our intake tract, is bad for our motors to consume. The oil fouls our plugs and o2 sensors... worse yet Oil has a lower flash point than gasoline... because of this, sucking oil into the intake or into the combustion chamber, can and does often lead to detonation under power. Detonation destroys engines.
Best advice I can provide and those that have done similar mods can provide, is to remove your PVCs and vent them into a separate catch tank that doesn't connect to your intake tract.
I personally recommend larger lines -12 at the absolute min and preferably -16 lines. The reason being that the smaller the hose, the higher the airflow through them and the more oil the air will carry... verse a large line with much lower air velocity and therefore much less likely to carry oil out of the motor.
A few examples of the pieces I built for Mark’s GT
Cheers
MoTeC Magic
Spectator
Thanks Kendall... I try to knock it out of the park when I do it... right or not at all
I made a handfull of these kits for both the GTs and GT500s if any of your customers are interested.
Cheers
- Jun 8, 2007
- 193
I have seen Evan's oil separator and if it was 2004, I'm sure Ford would be using this on all the cars. It looks OEM and if you wanted to take it off for some reason, there are no extra holes, or proof that it was ever used. It's an awesome 1 off American made piece, not a relabeled mass produced China piece.
MTV8
GT Owner
I would be interested in a kit that appears stock and contains all necessary lines and hardware.
Sinovac
GT Owner
:lol
Now that Lorenzo has successfully brought this thread back from the dead, has anyone used the Guyett Performance separator shown in post #24?
Now that Lorenzo has successfully brought this thread back from the dead, has anyone used the Guyett Performance separator shown in post #24?
BlackICE
GT Owner
I have one and like it because it looks the most OEM of anything I have seen. That matters when I get my bi-annual smog test, not having to remove a system that it obviously an add on.
Also Evan gives GREAT product support and service!
p.s. I know Ed Sims and GTED also have one.
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