Anyone run a breather in place of the oil cap?
- Thread starter nolyaw
- Start date
Have you done any type of ERG delete and thats why you added a breather?
If the breather is compensated for in the tune, it's not a problem.
A tune can't provide accurate adjustments to the air/fuel ratio, amongst other things, without an accurate measurement from the MAF, amongst other things. Unmetered air is just that, an unmeasured amount of air coming into the system. If, in this case, you leave the OEM PCV system in tact and add this oil cap breather, air will travel through the breather and eventually end on the intake tube side of the PCV system downstream from the MAF. This will cause a lean condition.
Running a breather on both sides, with an appropriate tune, is the only way to do a proper breather setup.
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I run the Steeda Oil seperator on the drivers side (PCV intact) and a breather in the Pass side! Never had problems. I had my car tuned like this and talked to my tuner about it, Not an issue at all. No oil comes out of it because there is no vacume pulling it out. This is hotly debated so I am not going to get into a pising match with anyone over it. All I can say is I dont have any issues and i run a consistant 11.8-11.9 AFR!
Run a breather now on each side, was tuned with an oil cap and the factory line back into the inlet tube with a JLT pre-filter, and an oil sperator, then added the breathers. No issues, just drove it 1800 miles.
Run a breather now on each side, was tuned with an oil cap and the factory line back into the inlet tube with a JLT pre-filter, and an oil sperator, then added the breathers. No issues, just drove it 1800 miles.
I don't understand what you are trying to do with your setup.
Whatever your reasoning, if the tube coming from the driver side PCV is still hooked up to the backside of the blower and lower manifold you are letting in unmetered air.
I cannot speak for his set up but I guess I let un metered air into the engine via the pass valve cover and my AF ratio is solid.
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Honestly, why not just drill some holes in the intake tube. After the MAF of course. :lol1:
In all seriousness, it is completely ridiculous that you are allowing this to happen. It is incredibly easy to meter ALL the air coming in. Wake up guys.
In all seriousness, it is completely ridiculous that you are allowing this to happen. It is incredibly easy to meter ALL the air coming in. Wake up guys.
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With a breather, crankcase vapors are not recirculated through the blower, intercooler, lower manifold, cylinder head, or combustion chamber like they are in the PCV system. Thus, the vapors don't "coat" the surfaces of your top end. They go straight to mother nature.
Well, if it's not environmentally safe, it's not going in my gas guzzling Cobra!!!
oke: Thanks for the explanation.
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Also, I have read many threads on the S197 forums about FI cars gaing like 30 whp when a breather system is employed. Actual back to back dyno comparisons.
Still trying to find out where D3 got that matching set of breathers!
Still trying to find out where D3 got that matching set of breathers!
How much un-metered air are we really talking about? If your tune is that close to the raged edge that the minute amount of air that can be drawn in through the breathers puts your engine at risk, you need a new tuner.
that is the First picture I've ever seen of a Cobra with a Breather on the oil cap??
Run a breather now on each side, was tuned with an oil cap and the factory line back into the inlet tube with a JLT pre-filter, and an oil sperator, then added the breathers. No issues, just drove it 1800 miles.
Hey D3,
I would like to ask the advantage of using the breathers,and also where you got them. You engine bay looks great!! Where in NC are you?
On the oil leaking subject. YES YES YES!!!!!! It leaks oil bad. I had a screw in breather for the oil fill cap also and it leaks. It runs down onto and into the alternator all over the oil filter, front crossmember and steering rack. after i put it on, about a week later i changed the oil and started to freak out thought my timing cover was leaking. I know that the alternators go bad all the time but im sure this didnt help mine out. when the alternator finally went south it was soaked in oil. now the only time that i put the breather in is for car shows.
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