Hey guys. I'm trying to eliminate the PCV hoses and aftermarket oil separator on my car because I think they're an eye sore. I've seen guys running the breather on the valve covers and I was just wondering 1) does that mean I can eliminate the rest of the PCV system including the PCV valve, and 2) does any oil make its way past those breathers? I'm worried about them being messy. Thanks in advance for any and all help.
Using Valve Cover Breathers
- Thread starter 04CYCOBRA
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I just converted mine to breathers. There's a hose coming from underneath the intake that you need to plug, along with one behind the blower. Plug those and the nipple on the inlet. Then just put breathers on and you're done. As far as mess, I've put about 300 miles on my car with them, about 10 wot pulls and haven't noticed much of any mess yet. The only thing I've seen was a small residue on one of my nitrous lines which runs right along side the breather but a quick wipe and it was gone. Here's a picture of mine, the passenger side one you cant see because I have a different style cover with the breather hole behind the plenum which just helps clean it up a little.
Ctgreddy I'm liking the engine bay. I'm going with the textured black theme myself.
Removing the PVC system eliminates the engines ability to purge the oil gas and water vapors that accumulate inside the crankcase contaminating the oil and forming varnish inside the engine. Just putting breathers on the valve covers will make the air inside the engine more or less "static" with nothing to draw the blow-by out of the engine where it will fester. Unless you have a vacuum pump to do this drawing thru the engine is the price to be paid to scavenge the crankcase. I would leave the PCV system in place.
Food for thought. Most engines outrun their pcv systems , in other words the blow by gasses are more than the pcv system can handle at full steam. When this happens the crankcase gasses just get pushed into the intake through the hose going to the inlet and the pcv valve . Why ? because supercharger or NA there is no vacuum when the throttle is on the floor this is the same time the most blow by gasses are produced. So when the crankcase is pressurized from blow by it will exit through the breathers causing the oil residue on the valve covers. I personally would run the pcv and fresh air ports from the valve cover to a breather tank to catch the oil. One it eliminates the pcv gasses which lower the effective octane of your fuel and two it keeps your intake cleaner on the inside. Ever notice the cams and cyl head under the valve cover look darker or varnished on the right side ? just so happens this is the side where the "fresh air inlet " to the engine is. The dark or dirty look is because the oil catches everything your air filter didn't.
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Well stated
There are both good and bad things associated with what ever you do even adding a vacuum pump. Not to worry too much regarding dirt getting past the breather. If you got a K&N air filter imagine what's happening there since they both use the same media :nonono:
Deal with the damn eyesore, dang it!!!! The PCV system tends to let a fine oil mist enter the blower intake and keep the lobes lubricated. It's not a good idea to delete the PCV system for that reason alone.
If you insist on a breather system, you won't have a messy motor with good quality breathers if your rings are in good shape and you don't have a lot of blow by. Be sure to plug the clean air intake to the passenger side valve cover on the air intake elbow, and the PCV vacuum hose that connects to the back of the blower. Otherwise you will have unmetered air entering the system and it will make the motor idle strange at least.
Heads up for the OP. I've tried breathers on a variety of cars including my Cobra and the oily engine blow by smell is noticeable. Maybe I'm just picky but when you have to drive with the windows up because it's a little cool out and you can smell that oily blow by smell coming through the vents then its not for me. I removed the breathers and went right back to PCV setup that recirculates the blow by into the intake to get burnt.
As for the blow by needing to be pulled from the crank case or else it forms varnish and and has an acidic reaction with the oil. Well I've read up a lot on that and can't tell if it's BS or just for emissions or holds any merit. I can tell you my personal experience on my turbo'd honda I built which I ran for 2 years as a daily driver. It had no PCV system. Instead the block and valve cover are just vented to a catch can which initially just had a breather but the smell coming into the cab of the car was killing me. So I ran a hose from the catch can all the way under the car to the rear bumper by the tail pipe and put the breather filter over there. I would still smell it once in a while but not nearly as bad.
Anyways after 2 years of daily driving that car and running it hard in boost I found no traces of sludge build up or anything else bad going on when pulling the valve cover and oil pan for inspection. Maybe 2 years of DD is not enough but I'd think if nothing has formed yet then nothing will. FYI I used mobil 1 full syn and changed the oil every 5k miles.
As for the blow by needing to be pulled from the crank case or else it forms varnish and and has an acidic reaction with the oil. Well I've read up a lot on that and can't tell if it's BS or just for emissions or holds any merit. I can tell you my personal experience on my turbo'd honda I built which I ran for 2 years as a daily driver. It had no PCV system. Instead the block and valve cover are just vented to a catch can which initially just had a breather but the smell coming into the cab of the car was killing me. So I ran a hose from the catch can all the way under the car to the rear bumper by the tail pipe and put the breather filter over there. I would still smell it once in a while but not nearly as bad.
Anyways after 2 years of daily driving that car and running it hard in boost I found no traces of sludge build up or anything else bad going on when pulling the valve cover and oil pan for inspection. Maybe 2 years of DD is not enough but I'd think if nothing has formed yet then nothing will. FYI I used mobil 1 full syn and changed the oil every 5k miles.
I've heard a few people on this forum say that which is the only reason I even tried it on the Cobra because from past experience I knew about the smell on other cars. Sure enough the Cobra had the smell too. Some get lucky I suppose.
No smell, no mess, no problems here.. been running my breathers for over a year now.
been running breathers for a few years now with no problems
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