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Valve cover breather kit help please....

Was about to buy a JLT oil seperator for about $120 but also ran into the Rehagan racing one for about $375.....and then noticed some people just using 2 K&N filters on the valve covers which would be about $40. Can someone please shed some light on the pro and cons of each? Thanks!
 
I would get a good breather kit, not sure how well the little filters do at relieving crank pressure. I am going with the kit YellowBoss makes that is probably the same thing Rehagan sells. I would rather go with this and spend the extra 100 bucks instead of two JLT's. I don't like how the JLT kits mount and also don't entirely like the Moroso kit since if you get two they are the same price as the 375 302S kit. I think also the people running just the filters are usually FI and can for some reason get away with this.
 
The K&N filters and YellowBosses's kit essentially do the same thing, which is open the valve covers to the atmosphere. But YB's is a little bit more environmentally friendly and less messy. since, it accumulates some of the oil in the can and guides all the oil accumulated in the lines back to the valves, because of the incline in the lines. Just putting on filters might make a mess in your engine bay, depending on how much they vent.

The JLT's are similar to the stock setup, but they accumulate some of the oil before the air gets recirculated to your intake. So, you may still recirc. some oil to your intake, since more than likely, the can won't accumulate all of the oil vapors.

I've seen some people add steel wool in their cans The steel wool increases the surface area the vapors can stick to, which may increase you filtering. I was going to do this to YB's setup, just to be more "green" lol (make sure the steel wool is secure and won't make its way to the valve covers!)

These are my thoughts on breathers, hope someone with more knowledge can chime in.
 

Grant 302

basic and well known psychic
Agree with F.D. above.

But want to add:
K&Ns will have the potential to make a huge mess underhood. Once the elements are soaked with oil, high RPM blow-by will puke it all over your coil and valve covers, and if there's enough, it can run down to your headers. Stay away IMO.

I prefer keeping the PCV intact for the street with a JLT or Moroso style filter, and either that or the 302S style catch/vent for the track. Vent style cans can be unpleasant to smell on the street.
 

Justin

Save the dawn for your dishes!!!
I run the morso can much better then the jlt in my opinion and the price is pretty good. the passenger side really isnt worth putting a catch can on as it hardly puts out any oil vapor.

here is the drivers side
http://www.americanmuscle.com/moroso-oil-separator-1112gt.html
and here is the passenger side if you want it (disregard american muscle miss labeling it as 05-10 GT as it will fit the 11-14's with the sound tube removed).
http://www.americanmuscle.com/moroso-oil-separator-0510gt.html

here is mine kind of hard to see.
1236155_648957895136785_1724504160_n.jpg
 
Justin said:
I run the morso can much better then the jlt in my opinion and the price is pretty good. the passenger side really isnt worth putting a catch can on as it hardly puts out any oil vapor.

here is the drivers side
http://www.americanmuscle.com/moroso-oil-separator-1112gt.html
and here is the passenger side if you want it (disregard american muscle miss labeling it as 05-10 GT as it will fit the 11-14's with the sound tube removed).
http://www.americanmuscle.com/moroso-oil-separator-0510gt.html

Justin didn't you mean the Drivers side is not needed? The passenger one is the one you should get. In Justin's picture he has the Passenger side Moroso can.

Chris
 
Cobra700 said:
Was about to buy a JLT oil seperator for about $120 but also ran into the Rehagan racing one for about $375.....and then noticed some people just using 2 K&N filters on the valve covers which would be about $40. Can someone please shed some light on the pro and cons of each? Thanks!

For more info and an answer to your questions with more info on this subject then you would ever want to know :eek: please read this very long thread:
https://trackmustangsonline.com/index.php?topic=880.0

Another thread with more info and lots of owners pics:
https://trackmustangsonline.com/index.php?topic=4593.0

Quicker FAQ's are here:
https://trackmustangsonline.com/index.php?topic=4593.msg76286#msg76286

Brandon302 said:
I would get a good breather kit, not sure how well the little filters do at relieving crank pressure. I am going with the kit YellowBoss makes that is probably the same thing Rehagan sells. I would rather go with this and spend the extra 100 bucks instead of two JLT's. I don't like how the JLT kits mount and also don't entirely like the Moroso kit since if you get two they are the same price as the 375 302S kit. I think also the people running just the filters are usually FI and can for some reason get away with this.

Thanks for your reply, if I may please correct a couple of things? First off you are correct just putting little filters is not a good way to go. It will create a mess in time with oil vapors, it will never pass any tech except the basic beginner track groups that do not check any cars and other small reasons.

The kit that Rehagen sells is the same only in the function of the canister. I am not going to into what is better or which you should get here. I am not a business and only offer these here are a favor to fellow board member. Dean runs a well established business and provides a service to many of this board's members and he is also a member. What I can say is last I checked the canister kit was not assembled, and requires drilling the firewall - I may be wrong. The canister setup I put together here was created and improved over a two year period by several site members. It evolved from a very plain looking setup that required drilling to mound to a refined product with braided lines and matching fittings along with an original design, no drill, mounting bracket.

If someone told you at some point you needed two oil separators like the, JLT type, they either do not understand how the PVC system works or they were lying. The hose on the drivers side connects fresh air from the airbox to the hollow fitting on the drivers valve cover. So the air is clean and passing into the engine. The only one that is needed with one of these "catch cans" that leaves the PVC valve intact in the passenger side.

F.D. Sako said:
The K&N filters and YellowBosses's kit essentially do the same thing, which is open the valve covers to the atmosphere. But YB's is a little bit more environmentally friendly and less messy. since, it accumulates some of the oil in the can and guides all the oil accumulated in the lines back to the valves, because of the incline in the lines. Just putting on filters might make a mess in your engine bay, depending on how much they vent.

I've seen some people add steel wool in their cans The steel wool increases the surface area the vapors can stick to, which may increase you filtering. I was going to do this to YB's setup, just to be more "green" lol (make sure the steel wool is secure and won't make its way to the valve covers!)

Again if I am may? I would not say the setup put together by me is more environmentally friendly, it is the same in the long run but the argument could be made that if the filters were used and oil built up inside the engine compartment it could drip to the ground, be washed off or rinsed off while driving in the rain. They will both vent top end blow-by gasses out to open air.

Adding steel wool will not help you in any way, in fact pieces of this could work there way into the crank case. Remember our setup is not a oil catcher or separator in any way, it is a vent to releave pressure build up once the PVC is removed. Yes sometimes oil will collect in the canister but it is normally very little and can be taken off and cleaned easily, the oil can then be disposed of properly instead of on the street as you drive.

Grant 302 said:
Agree with F.D. above.
I prefer keeping the PCV intact for the street with a JLT or Moroso style filter, and either that or the 302S style catch/vent for the track. Vent style cans can be unpleasant to smell on the street.

You are correct in your thinking. While some people will run this all the time the intent of our kit is to be used at off road and track events, the way the canister is made it can be removed in seconds and all your undamaged factory parts can be put back on for street driving or state inspection. The smell is something discussed in the threads linked above and also in the FAQ's


Thank you all for calling it the "YellowBoss" kit but the fact is this is a kit copied from Ford Racing, Grand Am and PWC cars. Then improved by several site member to look like it came that way from the factory and install without drilling in seconds. I may put it together but I have little to do with the design.
 

ArizonaBOSS

Because racecar.
Moderator
8,551
2,389
Arizona, USA
IMO the Rehagen-style setups are the best way to go as the oil simply CANNOT get sucked into the intake tract. More expensive but worth it, IMO. And HumbleYellowBoss builds a great kit.
 
ArizonaGT said:
IMO the Rehagen-style setups are the best way to go as the oil simply CANNOT get sucked into the intake tract. More expensive but worth it, IMO. And HumbleYellowBoss builds a great kit.

Do you know if the Rehagan also deletes the PCV?
 
ArizonaGT said:
The check valve on the passenger valve cover is replaced with a "straight-through" connector like on the driver's side.
Gotcha, looked up exactly what is referred to with PCV and I see now that you can't really remove the system.
 

Grant 302

basic and well known psychic
Brandon302 said:
Gotcha, looked up exactly what is referred to with PCV and I see now that you can't really remove the system.

That's not true. If the valve is removed, everything will vent just fine and the intake path is separated from the crankcase.

ArizonaGT said:
IMO the Rehagen-style setups are the best way to go as the oil simply CANNOT get sucked into the intake tract. More expensive but worth it, IMO. And HumbleYellowBoss builds a great kit.

This point should not be overlooked by anyone who tracks their cars. Going from WOT to lift for 20 to 30 minutes straight will pump a surprising amount of octane-reducing oil vapor though your intake tract. Filtering is more of a compromise for cars that are dual purpose.
 

TymeSlayer

Tramps like us, Baby we were born to run...
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Brighton, Colorado
Justin said:
I run the morso can much better then the jlt in my opinion and the price is pretty good. the passenger side really isnt worth putting a catch can on as it hardly puts out any oil vapor.

here is the drivers side
http://www.americanmuscle.com/moroso-oil-separator-1112gt.html
and here is the passenger side if you want it (disregard american muscle miss labeling it as 05-10 GT as it will fit the 11-14's with the sound tube removed).
http://www.americanmuscle.com/moroso-oil-separator-0510gt.html

How so is the Moroso better than the JLT? In you opinion...
 

Justin

Save the dawn for your dishes!!!
TymeSlayer said:
How so is the Moroso better than the JLT? In you opinion...
larger so it can hold more oil. has a hard mounting point under the STB. Easy to drain just put a small cup under it and twist the 1/4 turn valve. The early ones had crappy lines I give you that but they have since corrected that. I upgraded to AN lines and Fake looking AN fittings (hidden worm screws). I am going to do that trick with the steel wool in mine see if that collects more oil. if so it will have a much larger surface area for the oil to collect on.

I would do the "yellowbosskit" but I DD mine and would rather for go the oil smell in the cabin when you use the HVAC system. It sure does look nice though :)
 
Wow. Lots of info here. Especially links by Yellowboss. THANK YOU all for clarifying this. Looks like I'll be contacting humbleyellowboss in the near future for a kit. 8)
 

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