Building a Mustang GT: Why & When You NEED A Valve Cover Breather 

This is one of the best explanations of a PCV system. Thank you for creating and sharing this content

Until now most of us thought crankcase recirculation was just a way car manufacturers went by to abide by emission norms,now we understand the role of 2 vents crankcase and pcv and how they balance/regulate the pressure of an internal combustion engine,and the role a one way chk valve on the engine oil cap performs in releasing excessive pressure(which until now was thought to be vented via a crankcase breather) Thx so much Cameron for all the hardwork & research u went through for making us understand this and use this valuable information in our builds :)

Thanks Cameron for such a great job and putting in the long hours to explain this complicated subject to those who are interested in learning and understanding more about it! 🔥🍻

Just learned a new thing today. Thanks ✌🏼

Thanks for breaking it down! Very effective explanation

If you doubt the SVT engineers fix, simply use a unidirectional cap w/a latex cover. A trimmed latex glove works great. Late model Mustang works on my 04 Lightning

Had the upr version of this, leaked and swapped to pvc breathers instead. Great video and explanation thought

Love the videos keep up the good work I just got my 2017 mustang GT very exciting to start working on it and learning from your videos BTW love the ST build keep up the awesome videos 👍

Bro most excellent job. You explained everything so well. I watched the whole video and I didn't even need to. I'm a heavy duty diesel mechanic back in the day we used to let our blow by run out the valve cover and onto the ground. Now we have to use oil catch cans and blow-by filters. And with these big diesels when they start getting excessive blow by but they still run fine it creates problems with the turbo and liners and everything else and I was just trying to get a better understanding of how we could fix this problem to get another hundred thousand miles out of the truck. And thanks to you I now have a solution. Do the regulations I still won't be able to vent to atmosphere. But I can come up with a system that's cheap and effective to get that extra 100 or 200,000 miles out of the truck. Thanks.

Good informative video and I learned alot. I appreciate the work that went into this video. I have a catch can and I've seen people run this on their coyotes but never understood until now. Now I know what to buy when I supercharge my car

The more vacuum in the crankcase improves cylinder sealing, reduces blow-by. Race engine actually run a dry sump and vacuum pumps to keep high vacuum in the crankcase. The stock PCV system draws crankcase vapors through the cleanside during boost and open throttle by way of venturi affect of the velocity of the intake charge.. I have tested this breather. It does not function as described because of the low mass of the plastic nylon ball. . 10 seconds and piece of tissue will show that nylon ball is dancing around venting and allowing unmetered air into the engine even at idle. Remove the filter and see for yourself. Have the filter on top offers no resistance. This breather disrupts the normal build-up of vacuum in the crankcase by the PCV system, causing more gases, contaminents, and acids to build up. My little $80 OBDII tool showed a loss of of air reported by the MAF and a 8-10% increase in fuel trims, indicating unmetered air entering the system. This unmetered air is not healthy for your engine. The only way to get it to stop dancing around is to put my hand over it and sealing off so the PCV system can build enough vacuum to overcome the positive pulses. As soon as you disturb the vacuum or reduce it just by touching the throttle it starts venting again. All engines have pulses of positive and negative pressure due to the rotating crank and pistons. Hector at CFM admitted they have not done any testing and could not produce any data. GM has $15 valve regulated oil fill cap designed for this and does not vent at the slightest pressure. This cap will disturb the normal flow in the PCV system. CFM has the technology to put a manometer on the crankcase to fully test it but wont. I did with a $35 professional meter.

wow, what a perfectly constructed video man

This video is amazing man, I have a very high compression 5.7. And have been chasing the cause of a constant oil leak after fixing all gaskets. Hoping this allows some better breatbing😂

Great video. You explained it perfectly and simple 👌 thanks

Great job. Awesome! Get it 100%. Ordered this and I catch 10 for my Challenger Hellcat after watching your video. Great Content appreciate this. Keep up the good work.

Excellent video and explanation! Thank you.

I love learning ! Especially on my mustang 😊

Pretty awesome video. Thanks. Very informative

Just order mine buddy thank you for the video

Well explained

What about on a Naturally aspirated 4 cylinder? Specifically the ND Mazda MX5. I’ve seen people put it on them when they turbo them

Thanks for the info. Just ordered a CFM breather and catch can for my terminator. Also thanks for the 10% code

Great Explaniation Sir, Thank you.

Fanstatic information thanks for sharing

But assuming your valve stem seals are in good shape, any pressure coming from the crank-case to the valve cover is probably coming through the oil channels. If this is true, regardless if you're venting it from the top or not, it's affecting the flow of oil up to the head, and draining down from the head. There's supposed to be oil flowing through there, not blow-by vapor. So it would be ideal to find a way to add more venting straight to the crank case so that it doesn't have to pass up to the head. I don't want to drill holes in a good block, that sounds like asking for trouble. Maybe tape the oil pan, then have a tube on the inside that runs above the oil level?

Ford SVT addressed this condition by developing a PCV that never fully closes on Gen 2 Lightnings, assume any stock SVT models have same. Eliminates most if not all blow by. Replacing the PCV should be the panacea for excess contamination accumulation. So in theory the unidirectional filler cap wouldn't be necessary. I've got a bi directional filler cap w/a trap that has 0 volume in 3,400 mi.

Very informative

Get an oil catch can for the blow by on the PCv valve

PCV gives better Ring Seal, less wear on internals, less on no leaks thru seals on gaskets on engine blocks and obviously better emissions. But not alot of people know that you really need to have a breather drawing air into the engine while the opposite side valve cover relieves it into the intake manifold. Look at your common or garden '68 chevy smallblock - you will have the PCV hooked to the pipe in the base of the carby, and then on the passenger side you will have the breather connection which should go to a little plastic scoop inside the air cleaner with a foam membrane. It's a much more complicated but necessary system than one thinks.

It only took 3 minutes in in order to get the short summary .. that was fantastic.

Thank you

Nice job on your video and also you can put a couple drops of oil on the ball before installing.

Hi there I have a 2009 honda civic. It has lots of air coming out of the engine oil cap on idle once I unscrew it. Would it be better for now to just keep the engine oil cap off? I also tried to test the pcv valve and it seems like it was working. What would be the next alternative. The hoses seem fine tho if there was a rip i would think that would be able to feel the air soming out of the hose right? Thanks in advanced

Good video and good explanation, finale a RU-vidr from the same city, 🔧🧰🤙🏻

I have a 300 srt8 6.1 with a procharger but i have a problem when i start the car and step on the gas oil starts coming out from my header breather valve and so when i get to the stop light smokes starts coming out from the hood any suggestions to get that fixed?

That is a very informative video. Does the CCV on the Focus make a difference to this videos? My catch can for the pcv side is in the mail, a breather is to be advised I just learned. Will my engine not be covered in oil or other residue when the breather is letting pressure escape ?

awesome ! will help a ecoboost mustang ? (4cyl turbo) i've heard that they sometimes have problems with oil leaks on the turbo or somewhere around there, will this help with that ?

So i have an LS1, have the driver side valve cover capped. Valley cover running to catch can(no more breather) to intake manifold. Currently have passenger valve cover and throttle body plugged too.. my question is should I still run the (vent hose) from that passenger valve cover to throttle body or plugged okay? Also just installed this oil cap breather and deleted breather from catch can to eliminate unregulated air in.

Ight imma cop 👌🏽

Hey Cameron. Will I benefit from a valve cover breather is I am not going to boost my 2017 mustang gt. Thank you in advance. Excellent video btw. I am now a subscriber. Cheers

I got a brand new engine replacement from jasper in my 2014 chevy equinox which is stupid expensive I'm looking into putting on one of those with a oil catch can because the motor has a PCV valve design flaw it causes some serious oil consumption problems

Thanks for the lesson now I know what that mini filter is used for and mine is leaking oil I want to get a new one but I’m not sure if their universal or I have to get an specific one

Good stuff. So I need catch can and oil breather valve.

On a supercharged engine like the Coyote placing said breather you would have plug off the vacuum going to the supercharger inlet from the PCV. As well the clean side hose to the non metered hose on the intake tube and place a breather (non check valve) on the clean side, the pressure from the blow by at higher RPM will force dirty air back into the intake system thru the throttle body. I would for supercharged system block of original PCV system run a vented catch can on bank 1. And a vented filter on clean side. Only clean air gets into the intake system. The original clean side will block off as well. All crank case pressure will be routed to the vented catch can. And no check ball.

Thank you sooo much man you are the geat🌹

What about if the car comes with a turbo (new nissan altima vc 2.0 turbo) and how will affect the the boost will it have a lag/delay ? And can u still a blow off valve 50/50? To get the stu stu turbo sound ?

Hi when do you need to know the filter has to be changed plz let me know thanks

What if my c6 corvette ls2 it’s FBO but haves no turbo or super charge would you still recommend it? It have a oil catch can already

I think I’m getting a lot of blow by in my ST, I wanted to look into these

Nice video that i get my answer about the both side of intakes , but can we say this small filter isn't necessary because it just blow air so what is the problem if isn't on it ?

Man I've been trying to find one of those for my mazdaspeed 3 and nowhere will send one to New Zealand for me and here you are getting them for heaps of cars and I'm like where how haha

I put a filter on my pcv port on my 1uz and it didn't run good I could feel the vacuum from the intake I turned the car off after a minute do u think it's fine you think I hurt my engine?

Talking about PCv. I looked under my hood and I got a smalllesk on my pcv. I can see oil around it. What can I do ?

Can I still run this breather if I have a BOV??? Im running my BOV from the sound symposer delete plate on my intake manifold.

My dodge ram v8 has a breather on the passenger side of the engine between the air-box and the valve cover; is that doing the same thing that the oil-cap breather would do, and would it be a benefit to have both?

I run two filters. On my gen 2 coyote is this fine ? I have one on each PCV valve. Been on the car for awhile now and it runs fine

What about if you have a breather on your catch can and capped off the manifold?

I understand that two are not required, but any problem with two being installed? I currently have two K&Ns one on each valve cover, but not as cool seeming as these with a valve...at least from what I can tell is they are filters that might allow air both directions(???)

Where can I gee one exactly what I need thanks

Air intake one driverside, passenger side is caped by oil cap/filler. Is a catch 🛢 better in the place of the capped spot by oil fill? 2013 mustang gt procharger. Just ordered oil cap breather

Hey Cam do you know if it fits perfectly on a 2016 Mustang Ecoboost which has cover and oil cap is kinda in so wondering is it extended long enough to close a seal??? Also you don't need like a clamps to hold th breather cap,, I see the UPR one needs a clamps ??? Great video so informative Thank You ....

Subscribed. I learned a lot. . . I think🤔. . . I'm wrapping my head around it. Thanks for admitting that it took you a while to understand it. I think people THINK they know something, but when they try to explain it to someone else, they realize they don't really know (unless they're self aggrandizing) I just did an intake mod that deleted the breather tube just after the MAF and I replaced it with a little filter on the valve cover and couldn't understand why I'm lean only at idle. Now I get it. I'm pulling in un-metered air through that little filter. 😃 Knowing my problem is half the battle

We need a Happy Engine shirt design.

great video; does it work for porsche cayenne? my car is releasing constant fume on idle from pcv out

I have oil leaking from blow by. Would this relieve some blowby in this situation or should something else be done?

Can you put one on a turbo diesel?? Like a Jetta tdi?

i know its been a year but can i put a catch can even if i dont have a turbo setup?

So the Valve Cover Breather is better instead PCV delete method or use Oil Catch Can? Why? Isn't it better for pressure equalization and not to get oil into intake manifold use the PCV delete?

More easy if you have turbo just conect de pcv valve in the intake but 1 inch after pcv breather

I have a cherokee srt 6.4 not turbo no supercharger, only have cold air intake and repro you think i may need one?

Is there any issues on doing that on a stock engine?

Video starts at 2:27

Love this breather. What do I use to clean it. It's dirty

Have a question, is the fresh air inlet into the crankcase a one way valve(in) or is a open pathway? (air can go in or out)

do they have one for a gen 1 speed3? or is it the same as the gen 2?

I have one on my mustang and is leaks oil by the filter do u know why

Will a catch can with one of those breather filters on top of it work as well?

I’m Not sure if I should run a Oil Catch Can or a Breather Kit..Help! ? I have a 21 Mustang GT

I put a breather on scatpack by the MAF

illegal to vent any engine fumes or crankcase air to the atmosphere, that is why an oil seperator is better than a catch can as a seperator takes the oil and contaminates out of the crankcase waste and puts cleaner fumes back throught the intake to burn again.

Does this work for the ecoboost mustang?

Extremely laymans explanatory, which I appreciate! Now help me explain why my catch can fills up every 100mi (300ml) on a VW 2.0 TSI with 14% leak-down and 205 compression test.. lol Or why my new OEM stock PCV will syphon 1/2 qt of oil in 70 miles, and shove it down the engine's throat.. I cannot figure it out for anything..

I have a v6 charger 2010 but I’m not sure we’re to put it

Hey bro I don’t see one for 2020 gen3 10speed mustangs on the website?

Anyone order this part and the top filter just spin keeping it from turning all the way down??

Will you install oil catch can on your car?

Do you have them for the eco boost 2019

Do they have one for 2015 chevrolet silverado 5.3

How do I get that valve cover breather

pcv system not good on erquinox added breathert to avoid rear main seal blow out

Will they ship this to California?

so how did you get it? you live in california but i tried buying one and they wouldnt sell it to me.

So im okay putting this on stock motor?

Thoughts on a Audi A4 2.0 b7 ?

Would a catch can be needed after this?

I bought one from cfm and it’s been a week and I don’t have it...how long did it take for yours to come??

Any idea why my valve cover would explode into pieces?

Are you still running this or did you find it not to work right

Wrong it does not seal perfectly. You would have to develop 5-10inHg to start causing problems, you want a continuous vacuum of .1- .5 inHg. At ambient pressure in the crankcase you valve is closed, when under vacuum it is open if in fact you are using a true PCV valve not a PCV Orifice. The testing I have done has shown that crankcase vacuum is greatest at WOT, because of the fresh air side, actually it is called a Make Up Air Circuit. Have you heard of the Venturi affect, which all carburrators are design upon. Cameron have you done any crankcase pressure and fuel trim testing before and after you did this. That oil in the breather will drain back down into the crankcase, and will be adding oil every couple days. Yes, you have a pressurized intake but the stock PCV system will draw out the small amount of pressure in the crankcase, even when supercharged, through the intake manifold or when under pressure through the fresh air side ahead of you throttle body. It take 10-15psi in your crankcase to start causing problems and oil leaks so stop scaring people, yet that little ball inside will vent at fraction of .1psi. If you have that amount of pressure in the crankcase, you have serious problems with the piston rings. In fact HECTOR said it will vent at ANY pressure. Guess what, you have a constant fluctuation of pressure and vacuum in the crankcase. Any first year auto technician will tell you that, the key is you want a predominent negative pressure for best performance. Google "crankcase pressure wave form" and you will see. I made the same mistake when I young and dumb, until an old mechanic slapped me up side head and told me to learn and understand and test what I am doing, because these companies will lead you down the wrong path for a quick buck, and they sure did. Worse now you are spreading the same mistakes and misinformation to others. Do some testing of your own rather than talk theory. A Digital manometer only costs $35 a cap with a port on it and some tubing and you can do all the testing you want. Less than the cost of that cap.

Does it let oil smell to the engine bay?