PCV Valve vs Breather
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Ironic. i had one of the small filters stuck in the Oil filler neck hole. I noticed that there was some sort of liquid that would smear on the windshield at night. The last time I drove the car it was so bad that it was hard to see. popped the hood tday to find the little filter burn, layinfgon the header and oil all over the bottom side of the hood. I'm going to try to find one that fits better next time.
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i would think not. when i get new valve covers, im getting the ones with one hole in each then putting a breather in one, and a oil cap in the other. or maybe two breathers. then im gonna plug the pcv valve in the intake and the hose that is under the TB
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as I found out tonight, running a breather instead of the pass side vent tube messed up my fuel trims almost more than 20%. MY IAC count was down to 19 and my BLMs were close to 143. I took the breather out, and put the vent tube back on, and my IAC went up to 26 and the BLMS went back down to 129 and 131.
BTW like I mentioned that's a breather tube. THe PCV valve is on the driver's side in the intake.
Matt
BTW like I mentioned that's a breather tube. THe PCV valve is on the driver's side in the intake.
Matt
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our PCV is a true closed system. There is no reason to remove the PCV unless you like getting moisture in your valve covers. When you add a breather to the valve cover because of it's closed operation you are creating a small vacuum leak. Keep the PCV, it's not hurting anything. If you want to stock oil from entering the throttle body from the pass valve cover install an inline filter.
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always run a PCV system. it relieves crank case pressure with vacuum. this is a much better way than using a breather, you should do this with all V8s not just Lt1s. there was a long article in corvette enthusiast a month or two ago about PCV systems and their use and changes through out the years. it applied to corvettes mainly, but its the same for all V8s. also always have the PCV on the drivers side if you can help it. it allows the system to work better that way. unless the engine turns counter clockwise.
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the air comes in from the TB (which is metered), enters the pass side valve cover, runs through the intake to the PCV valve and then introduced into the intake. this is why it's a closed system. If you put a brether that your pulling in unmetered air which = vacuum leak.
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Combustion gasses that slip past even the best rings will linger in your crankcase and be very hard on the oil.
As far as ripping out the evap purge and EGR neither hurts power at all or weights that much, what has your ignorance lead you to believe you will gain? I can see getting rid of EGR with headers and a larger cam, a larger cam will self erg and not having to have the EGR fitting on headers just makes things a little easier.
As far as ripping out the evap purge and EGR neither hurts power at all or weights that much, what has your ignorance lead you to believe you will gain? I can see getting rid of EGR with headers and a larger cam, a larger cam will self erg and not having to have the EGR fitting on headers just makes things a little easier.
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is slightly less clutter worth it? without the purge selinoid your going to start smelling gas vapors soon coming form the canister. Why? for removing a 4"x4" selinoid?
The fact that you can put on a breather and say that it "seems" fine doesn't mean anything. Jus because you don't feel teh changes doesn't make it less real. Your car now has a mild vacuum leak. The fuel addaptives will correct for it but that gives you less room for error should another lean condition pop up.
The fact that you can put on a breather and say that it "seems" fine doesn't mean anything. Jus because you don't feel teh changes doesn't make it less real. Your car now has a mild vacuum leak. The fuel addaptives will correct for it but that gives you less room for error should another lean condition pop up.