CFM Performance Billet Valve Cover Breather Kit for 2002-2015 Mustang GT

[JeremyH]

Breathers for over 7 years now na and boosted stock motor and built. No complaints. Never needed to remove valve in the driver side cover.

My cfm oil neck breather def doesnt have a check valve and is always open. It does have baffling to prevent the phaser from slinging oil right out it.

 

[06 T-RED S/C GT]

Not only do you get great info, you get to spend stupid amounts of money buying stuff you really don't need.....wait, maybe that is just me.

Trust me, it's not just you lol. As I swore up and down that I'd stop after my last mod upgrade and now I'm spending more money upgrading the suspension..

It's just like an addiction

 

[06 T-RED S/C GT]

This just an FYI. I've ran a number of 3v supercharged setups. My experience is that the stock pcv system works just fine with forced induction. It's never caused any issues anyway, even up to 19psi.

The 3v crankcase ventilation system is designed to take air in from the passenger side and vent it through the driver side while keeping a vacuum on the system from the intake manifold.

People disagree on what's best for the motor. I'm of the opinion that the motor works best while the crankcase is under vacuum. The downside is that oil mist comes out with the crankcase air. An oil/air separator will go a long way to removing some of it but it won't get all of it. What does make it past the separator doesn't seem to affect anything.

I lived in the age of breathers on factory cars and don't want to go back, especially if it isn't necessary. The oil cap you referenced sounds like a good insurance policy to prevent overpressurization while still keeping the factory pcv system operational.

Bruce ! I totally agree 100% and share the same opinion as you do regarding how the motor works best while the crankcase is under vacuum.. IMHO the purpose of the PCV ventilation system is designed to evacuate crankcase gases from the crankcase in order to prevent contamination and sludge build up from taking place to begin with..

However there is a downside just as you mentioned in which the crankcase gases do get sucked into the intake manifold, even more so when running FI..

At first, I started out running the JLT oil separator and although it did remove a small amount of oil mist residue, there was still oil getting past the PCV connectors and into the intake manifold.. I later discovered it was due from the separator's inferior design that was the reason..

I then found out about the Bob's oil separator on the SVT forums and after reading all the positive reviews, I decided to give it a shot and I can honestly tell you that it really does it's job well.. It has a separate upper and lower chamber that includes both stainless steel filter mesh media and a stainless steel filter ring which prevent crankcase residue from reaching the PCV connectors at the intake manifold..

Since running the Bob's separator, I've checked the PCV connectors at the intake and also removed the throttle body on several occasions and all I've ever noticed was just a slight film residue at the PCV connectors, but no oily liquid residue whatsoever as both the throttle body and intake manifold have been completely bone dry, so once again the Bob's separator does seem to do it's job very well..

Shortly afterwards I came across the CFM oil cap breather and became interested in it's integrated/baffled one way check ball design and decided to give it a try to use as an insurance policy just as you mentioned in order to prevent over pressurization while still keeping the factory PCV system fully intact..

So far, it seems to be doing it's job, but won't know for sure until I get the chance to run the car at WOT under boost



-Rocky

 

[06 T-RED S/C GT]

I'll agree with this. I've had several GT500's and NEVER ran a catch can and never had any problems. Personally I think it's something you don't need. I did it on my 3v just to clean the engine bay up.

That's what I thought as well, until I noticed oil residue seeping from the throttle body and my intake tube.. But since adding the oil separator, there hasn't been any further problems..

You also mentioned you've had several GT500's and never ran across any problems and never had to use a catch can.. So the only solution I can possibly think of is the GT500's bottom end is designed to handle the additional cylinder pressure from running FI.. Where on the other hand, the stock 3v motor was never really designed for it to begin with

 

[06 T-RED S/C GT]

Breathers for over 7 years now na and boosted stock motor and built. No complaints. Never needed to remove valve in the driver side cover.

My cfm oil neck breather def doesnt have a check valve and is always open. It does have baffling to prevent the phaser from slinging oil right out it.

Jeremy ! Here's some images of my CFM oil cap breather.. If your's looks anything like mine ? It should also include an integrated one way check ball valve that will slightly rattle when shaken..


-Rocky

 

[lemkau77]

If your car is a GT500 ? which I assume is what you have ! Your PCV valve is located on the passenger side, opposite of the 3 valve 4.6 GT located on the driver's side.. Being that your GT500 is a 4 valve 5.4, this is why your PCV valve isn't located on the driver's side and would also explain the reason for noticing more oil on your passenger side filter..

My reason for trying out the CFM breather kit, is like yourself, I did not want to cut into the underside of my cam/valve cover in order to remove my PCV valve and as I mentioned earlier, it was my understanding that in order to run breather filters, the PCV system has to be completely disabled by not only capping off the vacuum lines, but also having to physically remove the PCV valve itself as well, otherwise running breather filters with the PCV valve still in place will only increase crankcase pressure build up due from the PCV valve not being able to allow enough airflow to flow out of the valve cover on it's own to vent the crankcase..

Perhaps the information I gathered was wrong ? but up until this point, it was really all I had to rely on at the time..

Supposedly the CFM breather has a one way check valve designed to properly vent the crankcase when under pressure, but at the same time is supposed to be fully compatible with the factory PCV system intact that will only allow air out, but not back into the crankcase as it opens during WOT or boost.. However under normal driving conditions and part throttle, the check valve is designed to stay closed while under PCV vacuum..

All I know other than what I've already mentioned, is the CFM breather kit replaces only the factory oil cap in order to vent the crankcase, but does not require disabling the factory PCV system nor does the company recommend running valve cover breathers.. Why, I don't know

I actually have the stock 4.6L, and unless I am mistaken I only have a PCV check on the passengers side. I don't know if there is any difference from the 06-08 valve covers. My CFM Breather does have the ball check that you are talking about. I chose to run full breathers on the car because I was getting oil on my throttle body and in my intake before I installed the supercharger. I wanted to prevent any chance of carry over.

 

[JeremyH]

Jeremy ! Here's some images of my CFM oil cap breather.. If your's looks anything like mine ? It should also include an integrated one way check ball valve that will slightly rattle when shaken..


-Rocky

Yeah mine does not. They may have revised it, I have had mine for awhile. You can shine a light through it, it just has the slotted baffles.

 

[07 Boss]

Quickly just to straighten some things out. When you run a PD blower the manifold is being pressurized after the PCV system so there really is not too much of a need to run breathers if you don't want to though I would always recommend a catch can. A centri or turbo will pressurize the system under boost and it doesn't flow the same with a pcv valve in.

That particular oil cap breather is really good for those applications because it will relieve any crank case pressure while under boost. and revert back to the stock system while under vacuum.

Now for those that run breathers without removing the PCV valve, that is OK but you are only using the other side to vent. In fact you don't even need a breather on the pcv side because nothing comes out of it. This oil mist and dripping on the valve cover is caused by this method because you only have the one small opening to vent. Removing the pcv valve now will give you two places to vent and less oil mist. Removing the pcv valve and running an oil cap breather with or without the check valve will prevent any oil mist because now you have 3 vents.

I run two breathers with the valve removed and a baffled (no check valve) oil cap breather. Never had an issue. The one thing to remember when you run breathers is to change your oil a little more often. The breathers are not as efficient at removing blow by as the stock system and that causes more un-burnt fuel and other things to dissolve back into your oil. Obviously this reduces it's efficiency and shortens the life.

And they look pretty.

 

[BruceH]

Bruce ! I totally agree 100% and share the same opinion as you do regarding how the motor works best while the crankcase is under vacuum.. IMHO the purpose of the PCV ventilation system is designed to evacuate crankcase gases from the crankcase in order to prevent contamination and sludge build up from taking place to begin with..

However there is a downside just as you mentioned in which the crankcase gases do get sucked into the intake manifold, even more so when running FI..

At first, I started out running the JLT oil separator and although it did remove a small amount of oil mist residue, there was still oil getting past the PCV connectors and into the intake manifold.. I later discovered it was due from the separator's inferior design that was the reason..

I then found out about the Bob's oil separator on the SVT forums and after reading all the positive reviews, I decided to give it a shot and I can honestly tell you that it really does it's job well.. It has a separate upper and lower chamber that includes both stainless steel filter mesh media and a stainless steel filter ring which prevent crankcase residue from reaching the PCV connectors at the intake manifold..

Since running the Bob's separator, I've checked the PCV connectors at the intake and also removed the throttle body on several occasions and all I've ever noticed was just a slight film residue at the PCV connectors, but no oily liquid residue whatsoever as both the throttle body and intake manifold have been completely bone dry, so once again the Bob's separator does seem to do it's job very well..

Shortly afterwards I came across the CFM oil cap breather and became interested in it's integrated/baffled one way check ball design and decided to give it a try to use as an insurance policy just as you mentioned in order to prevent over pressurization while still keeping the factory PCV system fully intact..

So far, it seems to be doing it's job, but won't know for sure until I get the chance to run the car at WOT under boost



-Rocky

I've run a JLT and it worked just as well as any of the other designs I've run. I stay away from SVT so mine worked just fine when I had it. There will always be something that gets by the can, understanding that is part of having a modified motor.

IMO the only time someone will run into issues is with a blow through setup. I've still managed to run pcv with a blow through. Everything ran just fine but I had an open breather on the passenger side with everything else hooked up. This allowed air to enter the motor so it could have proper vacuum. The driver side was still hooked up to the intake with two pcv valves just in case. This allowed the crankcase air to be evacuated under vacuum.

The big problem with how I had it set up was that I was allowing unmetered air in from the passenger side. Unmetered air is a no no because it's unexpected and can lead to lean conditions.

I'm fairly certain that the amount of air coming from the pcv system was very small in comparison to the air that freely comes through the intake system. IMO it's so small that it's really unnoticeable. Fuel trims easily took care of it during closed loop and nothing would be coming in under boost because the pcv valve would be shut off from the boost.

I really think that putting breathers on with forced induction is just another thing that was once needed due to large ring gaps, ptb clearance, etc., that was needed when machining tolerances were looser due to the old machining equipment. I keep my built motors to the tightest tolerances possible so that might be some of the reason I don't seem to be plagued with the issues others are concerned with.

Boost doesn't get by the cylinders and rings on the mod motors I've dealt with. One sign that the crankcase is being pressurized is having the oil dipstick push out under boost. If that isn't happening then you probably aren't having boost blow by the rings.

 

[06 T-RED S/C GT]

I actually have the stock 4.6L, and unless I am mistaken I only have a PCV check on the passengers side. I don't know if there is any difference from the 06-08 valve covers. My CFM Breather does have the ball check that you are talking about. I chose to run full breathers on the car because I was getting oil on my throttle body and in my intake before I installed the supercharger. I wanted to prevent any chance of carry over.

All 3v 4.6 engines have the PCV valve integrated under the driver's side valve cover, as the passenger side takes air in and then vents it through the PCV's driver side..

As far as I know, there were no valve cover changes from 06-08 that I'm aware of.. Also by any chance did you use a catch can before choosing to run full breathers on your car ? From what the folks over at CFM claim, is if you run their breather along with an air/oil separator, your able to vent the crankcase with the factory PCV system fully intact while the oil separator does it's job by preventing oil from getting on your throttle body and into the intake manifold..

Like yourself, I was also having the same problems with oil residue getting on my throttle body and into the intake manifold, so my original choice was to run full breathers as my solution.. However after I found out about the CFM design, this seemed like at least in theory the option I was searching for in finding a solution to relieve crankcase pressure without having to disable the factory crankcase ventilation system..

At first I had doubts, but after speaking with CFM tech support, I had a much better understanding behind their design concept and how the check ball valve functions with the factory PCV system still fully intact.. So I then made the decision to go this route rather than disable the factory PCV system in favor of running valve cover breathers..

So far, both the CFM breather and catch can seem to be working well together, however as I mentioned in a previous post, if the current setup doesn't work out ? Then I will end up making the switch to running full breathers..

 

[06 T-RED S/C GT]

Quickly just to straighten some things out. When you run a PD blower the manifold is being pressurized after the PCV system so there really is not too much of a need to run breathers if you don't want to though I would always recommend a catch can. A centri or turbo will pressurize the system under boost and it doesn't flow the same with a pcv valve in.

That particular oil cap breather is really good for those applications because it will relieve any crank case pressure while under boost. and revert back to the stock system while under vacuum.

Now for those that run breathers without removing the PCV valve, that is OK but you are only using the other side to vent. In fact you don't even need a breather on the pcv side because nothing comes out of it. This oil mist and dripping on the valve cover is caused by this method because you only have the one small opening to vent. Removing the pcv valve now will give you two places to vent and less oil mist. Removing the pcv valve and running an oil cap breather with or without the check valve will prevent any oil mist because now you have 3 vents.

I run two breathers with the valve removed and a baffled (no check valve) oil cap breather. Never had an issue. The one thing to remember when you run breathers is to change your oil a little more often. The breathers are not as efficient at removing blow by as the stock system and that causes more un-burnt fuel and other things to dissolve back into your oil. Obviously this reduces it's efficiency and shortens the life.

And they look pretty.

After reading over your post, you reminded me of a similar thread I submitted over on the Mustang Source Forums awhile back ago in which you also provided some very valuable feedback..

In the meantime, just wanted to say thank you once again for all your help and support..


-Rocky

 

[06 T-RED S/C GT]

Yeah mine does not. They may have revised it, I have had mine for awhile. You can shine a light through it, it just has the slotted baffles.

It would seem more than likely they did revise it Jeremy.. Being as your running full breathers, I don't think it's really necessary to upgrade to the latest version, but I also don't see any reason why you wouldn't benefit from it either

 

[06 T-RED S/C GT]

I've run a JLT and it worked just as well as any of the other designs I've run. I stay away from SVT so mine worked just fine when I had it. There will always be something that gets by the can, understanding that is part of having a modified motor.

Bruce ! just wanted to say I meant no disrespect regarding the JLT separator, as for some reason it just didn't work out for my particular application and therefore should had worded it that way in my previous post.

IMO the only time someone will run into issues is with a blow through setup. I've still managed to run pcv with a blow through. Everything ran just fine but I had an open breather on the passenger side with everything else hooked up. This allowed air to enter the motor so it could have proper vacuum. The driver side was still hooked up to the intake with two pcv valves just in case. This allowed the crankcase air to be evacuated under vacuum.

The big problem with how I had it set up was that I was allowing unmetered air in from the passenger side. Unmetered air is a no no because it's unexpected and can lead to lean conditions.

This was exactly my reason against running open breathers with the factory PCV system in place due to my concerns of unmetered air coming in through the crankcase and possibly leading to lean conditions..

I'm fairly certain that the amount of air coming from the pcv system was very small in comparison to the air that freely comes through the intake system. IMO it's so small that it's really unnoticeable. Fuel trims easily took care of it during closed loop and nothing would be coming in under boost because the pcv valve would be shut off from the boost.

I totally understand where your coming from and don't disagree, however I also didn't want to take such a risk, especially when I'm not really familiar with running additional PCV valves..

I really think that putting breathers on with forced induction is just another thing that was once needed due to large ring gaps, ptb clearance, etc., that was needed when machining tolerances were looser due to the old machining equipment. I keep my built motors to the tightest tolerances possible so that might be some of the reason I don't seem to be plagued with the issues others are concerned with.

Boost doesn't get by the cylinders and rings on the mod motors I've dealt with. One sign that the crankcase is being pressurized is having the oil dipstick push out under boost. If that isn't happening then you probably aren't having boost blow by the rings.

In that case, I can definitely rule out any unwanted crankcase pressurization for certain then

 

[Riptide]

You don't have to remove anything in order to run open filters. Everyone does it without touching the PCV. Just put filters on both valve covers and in place of the oil cap. Install vacuum caps on the intake ports. Done. Nothing to it.

Same here. I have K&N valve cover breathers and a CFM. Intake capped. That's it.

I smell a little oil vapor sometimes but I've not had to clean anything up yet. I'm not nice but I don't beat the hell out of the car either.

 

[BruceH]

Bruce ! just wanted to say I meant no disrespect regarding the JLT separator, as for some reason it just didn't work out for my particular application and therefore should had worded it that way in my previous post.



This was exactly my reason against running open breathers with the factory PCV system in place due to my concerns of unmetered air coming in through the crankcase and possibly leading to lean conditions..



I totally understand where your coming from and don't disagree, however I also didn't want to take such a risk, especially when I'm not really familiar with running additional PCV valves..



In that case, I can definitely rule out any unwanted crankcase pressurization for certain then

I didn't take it bad. I did notice awhile back that all of a sudden people were down on the JLT separator and from what I understand it started on SVT. For all I know I just didn't pay enough attention to it when I had it. I'm currently running a full size Moroso and can say it catches about the same amount as the JLT did with this motor while na.

We all have different ways of thinking about this stuff and we all have to make decisions as to what we think is best for our car. We also have to pay the price when something doesn't work like we thought it would. I'm usually the skeptic when it comes to improving something that's working fine for me, it's just how I am.

The double pcv was nothing more than keeping the driver side pcv in the valve cover and adding a motorcraft ball type valve to the hose between the intake manifold and drivers side valve cover. It's something Paxton includes with their setups. In theory the factory pcv should keep the boost out. The extra ball valve makes sure the factory pcv isn't subjected to boost.

Back in the day of factory breathers people would put vacuum pumps on the motor for better performance. IIRC a good vacuum pump was supposed to free up about 40hp on a highly modified motor. The reasoning was that the motor was fighting itself without that crankcase vacuum. Now that we have factory vacuum pumps via the pcv people put breathers on. I think we are hard wired to change things.

 

[lemkau77]

All 3v 4.6 engines have the PCV valve integrated under the driver's side valve cover, as the passenger side takes air in and then vents it through the PCV's driver side..

As far as I know, there were no valve cover changes from 06-08 that I'm aware of.. Also by any chance did you use a catch can before choosing to run full breathers on your car ? From what the folks over at CFM claim, is if you run their breather along with an air/oil separator, your able to vent the crankcase with the factory PCV system fully intact while the oil separator does it's job by preventing oil from getting on your throttle body and into the intake manifold..

Like yourself, I was also having the same problems with oil residue getting on my throttle body and into the intake manifold, so my original choice was to run full breathers as my solution.. However after I found out about the CFM design, this seemed like at least in theory the option I was searching for in finding a solution to relieve crankcase pressure without having to disable the factory crankcase ventilation system..

At first I had doubts, but after speaking with CFM tech support, I had a much better understanding behind their design concept and how the check ball valve functions with the factory PCV system still fully intact.. So I then made the decision to go this route rather than disable the factory PCV system in favor of running valve cover breathers..

So far, both the CFM breather and catch can seem to be working well together, however as I mentioned in a previous post, if the current setup doesn't work out ? Then I will end up making the switch to running full breathers..

I will have to check it out next time I'm out by my car. I did not run a catch can previously, I had heard/read about too many separators that would still allow vapor to be carried through. I just decided to avoid all possibilities of carryover. I'll see how I like the breathers over this next summer and go from there if I change my mind.

 

[06 T-RED S/C GT]

I didn't take it bad. I did notice awhile back that all of a sudden people were down on the JLT separator and from what I understand it started on SVT. For all I know I just didn't pay enough attention to it when I had it. I'm currently running a full size Moroso and can say it catches about the same amount as the JLT did with this motor while na.

When it comes to SVT ! Nothing really surprises me at all.. I joined that site back in October and so far haven't had much support from anybody, in fact I've had far more feedback and support in just 2 days since joining this site than I have in 3 months over on SVT.. Needless to say, I know which site I'll be spending the majority of my time from here on in

We all have different ways of thinking about this stuff and we all have to make decisions as to what we think is best for our car. We also have to pay the price when something doesn't work like we thought it would. I'm usually the skeptic when it comes to improving something that's working fine for me, it's just how I am.

That's pretty much the type of person I am as well..

The double pcv was nothing more than keeping the driver side pcv in the valve cover and adding a motorcraft ball type valve to the hose between the intake manifold and drivers side valve cover. It's something Paxton includes with their setups. In theory the factory pcv should keep the boost out. The extra ball valve makes sure the factory pcv isn't subjected to boost.

Back in the day of factory breathers people would put vacuum pumps on the motor for better performance. IIRC a good vacuum pump was supposed to free up about 40hp on a highly modified motor. The reasoning was that the motor was fighting itself without that crankcase vacuum. Now that we have factory vacuum pumps via the pcv people put breathers on. I think we are hard wired to change things.

I've actually read on other sites that some people run breather tanks and connect them to vacuum pumps in order to evacuate and vent the crankcase more efficiently..

The way I see this is overkill, as it's just like you mentioned.. We have factory vacuum pumps via the PCV for that reason..

So in your opinion, would you recommend running a double pcv for my particular application or just leave well enough alone as is ?

 

[BruceH]

When it comes to SVT ! Nothing really surprises me at all.. I joined that site back in October and so far haven't had much support from anybody, in fact I've had far more feedback and support in just 2 days since joining this site than I have in 3 months over on SVT.. Needless to say, I know which site I'll be spending the majority of my time from here on in



That's pretty much the type of person I am as well..



In your opinion, would you recommend running a double pcv for my particular application or just leave well enough alone as is ?

You have a pd (positive displacement) blower. Like earlier mentioned it means that your pcv isn't subjected to boost because it plugs in before boost enters the picture.

I think you will be fine with the factory setup. I ran a Whipple at one time and kept the factory pcv system. A can was added but that was it. Ran a max of 17psi without issue.

The only time the pcv will be subjected to boost pressure is with a centri or turbo because they pressurize before the throttle body which means the intake manifold will be under boost pressure. Having the manifold under pressure means that boost will be pushing against the pcv.

Now that I think of it I haven't really looked at a Saleen setup in detail, I'm assuming that your pcv plugs into the manifold before the blower like every other pd setup that's out there. Provided that's the case then you will be fine with the stock pcv since it will never see boost.

 

[06 T-RED S/C GT]

I will have to check it out next time I'm out by my car. I did not run a catch can previously, I had heard/read about too many separators that would still allow vapor to be carried through. I just decided to avoid all possibilities of carryover. I'll see how I like the breathers over this next summer and go from there if I change my mind.

The first catch can I tried out, still allowed crankcase vapors to pass through the PCV lines, into the intake manifold and then seeped out from behind the throttle body and into my intake tube..

Personally I have nothing against the JLT separator, however it just didn't work out for my particular application..

So I ended up sending it back and was actually going to switch over to breathers until I found about the Bob's oil separator.. Since making the switch over to the Bob's can, both my throttle body, intake manifold and intake tube have been completely bone dry for the last 5 months..

Although I'm still a bit skeptic, the Bob's can does seem to be doing it's job fairly well, at least up to this point anyhow..

 

[06 T-RED S/C GT]

You have a pd (positive displacement) blower. Like earlier mentioned it means that your pcv isn't subjected to boost because it plugs in before boost enters the picture.

I think you will be fine with the factory setup. I ran a Whipple at one time and kept the factory pcv system. A can was added but that was it. Ran a max of 17psi without issue.

The only time the pcv will be subjected to boost pressure is with a centri or turbo because they pressurize before the throttle body which means the intake manifold will be under boost pressure. Having the manifold under pressure means that boost will be pushing against the pcv.

Now that I think of it I haven't really looked at a Saleen setup in detail, I'm assuming that your pcv plugs into the manifold before the blower like every other pd setup that's out there. Provided that's the case then you will be fine with the stock pcv since it will never see boost.

Yes ! that's correct Bruce.. The Saleen set up is no different from any other PD set up that's still in production.. So yes, the PCV does plug into the manifold port before the actual internal components of the blower itself..

But here's what I still don't quite understand though.. What was causing the crankcase oil vapors to pass through the PCV plug in connectors into the intake manifold and throttle body.. Is it from increased cylinder pressure or is it crankcase pressure from the Saleen blower that's causing the oil vapors to pass through the PCV ventilation system ? Other than that, I honestly cannot figure out what else it could possibly be that would make any logical sense IMO