Breathers, PCV question

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A56 said:
Anyone have any experience with oil separator's tied into the pcv ?
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I have in my Neon, they have a pretty goofy system. Look at some track cars, they run PCV but raise and plumb the breather and PCV a farther distance and add couple bends than factory to give the oil a better chance to to separate out and return to the crankcase.
 
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AJ/FormS said:
On the street,
if your engine can spin the tires for most of first gear;then your engine already has more power than the chassis can handle; so, in that case you don't need more power;and if you have blow-by, then fix the engine.
My idea is to forget the E-vacs. Been there done that.

But if I had a modest-powered track-car;
I would find a better place to pull cc air from, rather than the valve covers.
IDK what the big-boys do.....
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The big boys use pan evacs , or vacuum pumps , ''to high dollar for me'' . I have supposedly a 700 plus h.p. engine , according to comp. programs and that crap , doesnt feel like it to me . Dont have the tires and gears of the cars of my past tho.
With forward j bars , tied to the shock towers in 2 places ,a 505'' engine w/ raised port heads on a motor platre , and TTI headers , things are tite as h---- in there .
 
66fs said:
I have in my Neon, they have a pretty goofy system. Look at some track cars, they run PCV but raise and plumb the breather and PCV a farther distance and add couple bends than factory to give the oil a better chance to to separate out and return to the crankcase.
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Have never had a problem oil out of the the valve cover breathers or pcv system with oil , i even built a site tube catch can , didnt get anything and took it back off.
 
66fs said:
So where is your highest vacuum reading? It is not at WOT.
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Idle to about 4500 , havent been able to watch it at wot , should be the lowest to none there , gets too hairy on the street to watch a gauge much .
 
famous bob said:
Have never had a problem oil out of the the valve cover breathers or pcv system with oil , i even built a site tube catch can , didnt get anything and took it back off.
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Me either, but if you have blowby, it is nice not to be oil fogging your intake charge.
 
I take it u arent
yellow rose said:
You can run pan evacs with mufflers, and like everything else you have to do it correctly.

I run a closed system with a PCV and pan evacs and mufflers.
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I take it u arent using a pcv with those ------------??
 
famous bob said:
Idle to about 4500 , havent been able to watch it at wot , should be the lowest to none there , gets too hairy on the street to watch a gauge much .
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Yeah, usually at cruise. Next to nothing at WOT. I was just trying to point out that the PCV is not a vacuum leak when you need need it most. The opposite of what was pictured.
 
66fs said:
Yeah, usually at cruise. Next to nothing at WOT. I was just trying to point out that the PCV is not a vacuum leak when you need need it most. The opposite of what was pictured.
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Yeah, I didn’t understand that picture myself.

And to your point about WOT, FB and I both use a PCV and pan evac. That way, at WOT you have something pulling negative pressure in the crankcase.
 
You guys are way above me. I just have a quick street car. Factory stuff works fine for me. I even run factory exhaust manifolds and straight thru single exhaust.
 
Whatever you do, DO NOT tee into the PCV line;
Firstly the line is probably too small, but more importantly;you will not be sucking totally from the CC anymore. Now you will be mostly sucking out of the plenum, and throwing it into the exhaust system, which is hot enough to set it on fire instantly, and I can't imagine what that will do to your overlap cycle, except to say; it probably would not be good,lol.
Plus I can't imagine the tuning problems you would have because my E-vacs pulled real hard at idle already.
IMO; you can't take shortcuts with those, they need a dedicated flow circuit. Mine worked so good, they sucked air at the rear main seal.Which is the main reason I ditched them. If there was a power difference, my butt-dyno never noticed. My BFGs spin,IDK, 7 seconds at least, at WOT. I think maybe I need a smaller carb,lol.
 
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AJ/FormS said:
Whatever you do, DO NOT tee into the PCV line;
Firstly the line is probably too small, but more importantly;you will not be sucking totally from the CC anymore. Now you will be mostly sucking out of the plenum, and throwing it into the exhaust system, which is hot enough to set it on fire instantly, and I can't imagine what that will do to your overlap cycle, except to say; it probably would not be good,lol.
Plus I can't imagine the tuning problems you would have because my E-vacs pulled real hard at idle already.
IMO; you can't take shortcuts with those, they need a dedicated flow circuit. Mine worked so good, they sucked air at the rear main seal.Which is the main reason I ditched them. If there was a power difference, my butt-dyno never noticed. My BFGs spin,IDK, 7 seconds at least, at WOT. I think maybe I need a smaller carb,lol.
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If ur spinniung that much , u need bigger tires or to work on ur chassis . I prefer mine to leave --------
 
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