Catch Can Chapter 63

[5ABI VT]

many years ago when I built my first high rpm solid roller for my vette I thought it was interesting to add that I was sending oil samples to blackstone labs. WHen I switched to the breathers their response surprised me. The said it appeared I switched to a breather or did away with the pcv system? If not check the system or pcv valve etc. My oil had 45x the contaminants my previous sample had and thats with a 3500 mile oil change. After reading up on the subject on bitog and other forums etc I finally understood the setup and how it functions. Its worth keeping

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[Ultrakla$$ic]

ruh roh..........

 

[rredd14]

can i get a link to a breather kit? I cant seem to google anything

www.jpcracing.com/2011-gt-boss-breather-package

 

[rredd14]

ruh roh..........

ooooooopppppssssss! been doing it since the 80's!

 

[Trackaholic]

I have the UPR GT350 catch can setup, and this is what it captured after a Trackday @ Sonoma plus 3000 street miles. Almost certain that 90% was from the track day:

I had a friend with a Viper who had a "burp" of oil go through his PCV system, fouling his MAF and causing his engine to go into limp mode while exiting a turn @ Buttonwillow. The sudden loss of power could be a real hazard at the track. One of the Viper engineers told him that this was a known issue on his year of car, that has since been fixed with more baffling, but that he should run a catch can to prevent any future occurrence.

IMO a catch can is useful for DI engines to help reduce oil on the valves, but is really only needed on a Port Injected engine if you are tracking and pulling high lateral G's that can cause oil to pool in strange places.

I am not a fan of breathers, but in CA I don't have an option for them anyway (at least to remain CARB legal). A catch can is OK since it maintains the PCV system and doesn't vent to atmosphere. The breathers do look pretty nice though, since they really clean up the look of the engine bay by eliminating quite a bit of plumbing.

-T

 

[GT Pony]

^^^ That's a lot of caught oil. Obviously, when the engine is pushed really hard, like during a track event, the amount of oil that could go in to the intake manifold is rather large.

 

[sk8erord]

^^^ That's a lot of caught oil. Obviously, when the engine is pushed really hard, like during a track event, the amount of oil that could go in to the intake manifold is rather large.

The GT is port injection, though, right? So the bigger issue is the blow-by reducing octane rating more than caking the valves, right? Versus a DI car where the valves don't get cleaned by fuel/additives?

 

[Trackaholic]

The GT is port injection, though, right? So the bigger issue is the blow-by reducing octane rating more than caking the valves, right? Versus a DI car where the valves don't get cleaned by fuel/additives?

I am not really concerned about effective octane or street performance, but on the track I like having the peace of mind that a large bolus of oil getting through the PCV system isn't going into my intake and therefore won't potentially cause an issue with the MAF.

Ford Performance does recommend separators on the GT350 (and they've conveniently developed their own kit...hmmmm - but they also were running them during the GT350 press events using aftermarket kits).

-T

 

[sk8erord]

I am not really concerned about effective octane or street performance, but on the track I like having the peace of mind that a large bolus of oil getting through the PCV system isn't going into my intake and therefore won't potentially cause an issue with the MAF.

Ford Performance does recommend separators on the GT350 (and they've conveniently developed their own kit...hmmmm - but they also were running them during the GT350 press events using aftermarket kits).

-T

Ah, I didn't even think about the MAF. On my EBM, octane rating was one of the concerns due to the increased risk of knock with the lowered octane rating. Seems that would still be a concern, especially if tracking the car. I'm putting one on my for peace of mind, anyways. GT is a new animal for me, though. First V8 I've ever owned, and the last NA car I had was my '96 V6. Everything since has been turbo 4, so... LOL

 

[CoyoteFiveO]

The kit from JCP comes with caps and clamps.

From the pictures i don't see any caps?

A lot of the deposits are also from overlap situations when the piston pushes exhaust back into the intake manifold when the intake valve is open during some of the exhaust stroke. Coupled with oil on the cylinder wall it's going to get some poop in the intake runner and on the exhaust valve. Of course the port injected motors help keep that clean by spraying the valve with fuel and detergents before it opens (and DI engine do not).

I've used a ton of catch cans since around 1999 and none of them made a difference even though all of them "caught oil." There is a huge misconception that oil in the catch can means no oil in the intake manifold....the only way to eliminate it is by using open filters on your valve covers, which is smelly, or using a vacuum pump into a catch can with an open filter, which is smelly, but works great and can free up 20 or so HP. Passive cans are for the birds. Do it right or leave it alone, IMO.

And no, "something is better than nothing" is not true.

So i have a bobs CC already and have not installed it. Would you recommend installing it or running breathers instead? My car is a daily driver and I'm not a huge track racer. More for my pleasure and when some one pulls up along side of me.

 

[RockStang]

Just installed the breathers with my ProCharger kit. We'll see how it goes. I will say that they saved a lot of large tubing from running through the engine bay.

 

[Higgs Boson]

From the pictures i don't see any caps?





So i have a bobs CC already and have not installed it. Would you recommend installing it or running breathers instead? My car is a daily driver and I'm not a huge track racer. More for my pleasure and when some one pulls up along side of me.

It's a toss up. On a daily driver I just run the stock PCV unless you are FI and the stock PCV can't keep up then run breathers. A stock or bolt on daily driver would be best suited to the stock PCV, IMO. Running a catch can isn't going to hurt anything but it's also not going to do anything either.

Already having the catch can is a "sunk cost" so it's irrelevant.

 

[GT Pony]

I Running a catch can isn't going to hurt anything but it's also not going to do anything either.

If catch-cans didn't do anything, then they wouldn't be catching any oil. Good ones catch quite a bit of oil actually.

 

[Higgs Boson]

If catch-cans didn't do anything, then they wouldn't be catching any oil. Good ones catch quite a bit of oil actually.

Can you prove they don't create the environment whereby oil is more readily drawn out of the crankcase due to the introduced restriction in the system?

Can you verify the amount of water vapor vs oil that is actually caught even though it's assumed that if its in the can it must be oil?

Can you explain why you will still have oil in your intake manifold after installing and using a catch can?

Do you think that "catching some oil is better than catching none?"



I do think they are of some use in certain applications but daily driving with the occasional romp, which is 98% of the cars sold, they are useless. And in the 2% where a catch can might be of use, two breathers are much better.

 

[GT Pony]

Can you prove they don't create the environment whereby oil is more readily drawn out of the crankcase due to the introduced restriction in the system?

If anything, adding a catch-can adds to the flow restriction on the PCV system and you'd think that would actually cut down on the flow and the amount of oil caught, but it doesn't seem to. The flow through the PCV system is very low, so a little more restriction in the system doesn't seem to affect it at all from my experience.

Can you verify the amount of water vapor vs oil that is actually caught even though it's assumed that if its in the can it must be oil?

I've seen some photos posted where the catch-can has both oil along with some water that was caught. I would imagine on a short trip on a cold day the can probably does catch some water vapor that might condense out. If there is water vapor in the gasses being sucked out of the engine and into the can, there's the possibility for water to condense. If it doesn't condense in the catch-can, then it goes into the intake manifold. Water vapor back into the intake isn't as bad as oil vapor into the intake.

Can you explain why you will still have oil in your intake manifold after installing and using a catch can?

Because no catch-can is 100% effective. I'd say a good catch-can is probably in the 80~90% effective range. I guess I'd still only want 10~20% of what could have gone into the intake verse 100% without a catch-can.

Do you think that "catching some oil is better than catching none?"

Of course, don't you? See answer above.

I do think they are of some use in certain applications but daily driving with the occasional romp, which is 98% of the cars sold, they are useless. And in the 2% where a catch can might be of use, two breathers are much better.

I guess I have to disagree. I just drive my GT 'spirited' on the streets but usually just cruising around normally like a daily driver would be, and the catch-can seems to catch a fair amount of oil that would otherwise go into the intake manifold for no good reason.

IMO, breathers might be good to install for only full out race track use. Running open breathers on the street is not good IMO because the crankcase is not getting fully evacuated and cleaned of nasty shit like it would with a functioning PCV system.

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