oil catch can install

[Boostedstr8six]

I have mine installed just under the intake manifold. I think I have a pretty good plumbing set up as well.

The accordian hose port is tied to the TB port on the outlet side of the CC, with a check valve on the TB line to keep boost out of the PCV system. The valve covers, of course, connect to the inlet of the CC.

I'm thinking of adding a check valve to the accordian line so when off boost the TB vac is isolated to just pull through the CC and not from the accordian line too. Then, when under boost, the TB valve will close and the accordian line valve will open. Sounds like it would work, eh?

I'm actually trying out an oil/water trap (slightly modified) for air compressor systems and it seems to be working. I did remove the internal filter as it clogged almost immediately with oil/water and I had the spy hunter thing going on.

 

[starscream5000]

Do you have a picture or a link to a check valve like what you are using?

 

[TurboWarrior]

ok now that i know its wrong im redoing it. I have an idea ill post in this thread when im done

 

[boostadikt]

you see the most crankcase pressure when your under boost.. so isn't it more important to have the line pulling air in front of the turbo than to have the one on the TB, because you dont see much pressure when your under vacuum.

I dont have mine running to either, the PCV goes into the can and it is just vented with a filter....... Whats wrong with this type of setup? im not going for emissions, just clean and simple, and its been working so far.

 

[josh930]

The correct way to do it then is to tee in the TB port, both nipples, going to inlet of catch can, then to the accordian hose right? How much vapor travels back into the TB when not in boost do you think?

Will this work ok because I have my TB blocked off as well and its there for a reason so I really never felt right blocking it off.

 

[TurboWarrior]

I was thinking just to run that TB port over T to the valve cover ports as it goes over. Like stock. Then plug one of the ports on the catch can. I think that would take advantage of the airflow the most.

 

[starscream5000]

Maybe someone who actually knows the correct way to do this will chime in soon .

 

[hottscennessey]

IMHO, if you're not running a catchcan, leave it like stock..

If you are, block the throttle body port, and run an individual line per valve cover to a catchcan (catchcan must have 3 inlets).

Run your third line to your turbo inlet pipe, feel free to use a larger line as to put more vac. on the catchcan. This will give you vac at idle (not as much as the TB port, mind you, but pleanty of vac. under boost..when it's really needed. All this without making a boost leak)

You can never have too much vac. on the crankcase (or at least thats what IJ says).

If you have a catchcan with only two ports, you can tee the lines comming off the valve cover... send that line to the catchcan, and send the other line between the catchcan inlet and the turbo inlet pipe. With this method you may still have some problems with not having enough vac. on the crankcase, but only if your motor is worn.

 

[staticpat]

EDIT: Most people do it the way hottscenney describes, but as he says there will be little to no vaccum during some situations.

The "correct way" is to route it like stock, but some people fear it working like a boost leak under high boost situations. I would only worry about it if you have alot of volume to fill in your pcv plumbing/can.

I was looking at an SRT-4 (say what you will but they are engineered for high boost) bay today and got an idea. They run one valve cover to the intake manifold with a check valve inline (so it will pull vaccum when not under boost but close when the engine is boosting. The other valve cover is run to the turbo inlet pipe. This way when the check valve is closed (under boost) on the first line the crankcase pressure will go through the second line which will have high vaccum (when under boost).

To adapt this to our setup we would just keep the stock routing but add a one way check valve (PCV valve aha) between the intake manifold and the valve cover. I guess its not "positive" crankcase ventilation but his would have a vaccum source always readily available and would not work as a boost leak.

I'm sure jetjock will tell me I'm wrong but it makes sense to me!

 

[starscream5000]

I have mine installed just under the intake manifold. I think I have a pretty good plumbing set up as well.

The accordian hose port is tied to the TB port on the outlet side of the CC, with a check valve on the TB line to keep boost out of the PCV system. The valve covers, of course, connect to the inlet of the CC.

I'm thinking of adding a check valve to the accordian line so when off boost the TB vac is isolated to just pull through the CC and not from the accordian line too. Then, when under boost, the TB valve will close and the accordian line valve will open. Sounds like it would work, eh?

I'm actually trying out an oil/water trap (slightly modified) for air compressor systems and it seems to be working. I did remove the internal filter as it clogged almost immediately with oil/water and I had the spy hunter thing going on.

What I'd really like to see is JJ's opinion on this method as this is the first time I've heard of it done, this way (and that doesn't mean it's wrong by any means).

 

[TurboWarrior]

IMHO, if you're not running a catchcan, leave it like stock..

If you are, block the throttle body port, and run an individual line per valve cover to a catchcan (catchcan must have 3 inlets).

Run your third line to your turbo inlet pipe, feel free to use a larger line as to put more vac. on the catchcan. This will give you vac at idle (not as much as the TB port, mind you, but pleanty of vac. under boost..when it's really needed. All this without making a boost leak)

You can never have too much vac. on the crankcase (or at least thats what IJ says).

If you have a catchcan with only two ports, you can tee the lines comming off the valve cover... send that line to the catchcan, and send the other line between the catchcan inlet and the turbo inlet pipe. With this method you may still have some problems with not having enough vac. on the crankcase, but only if your motor is worn.

Thats exactly how mine is. Its the least amount of connections that way.

What is the negative side of the system not functioning perfect?

 

[hottscennessey]

Smoke, blowing seals out, and gunk in the engine are symptoms of a PCV system not doing it's job.

I've also seen a crappy PCV system kill turbos, and shortly after that kill rod bearings. You can tell because of how quickly the oil becomes blackened/expired.. this is a SERIOUS problem that must be addressed immediately.

If you suspect problems send your oil in for analysis (at a reputable shop like blacksone).

 

[Spaniard]

How about this setup for my 1JZ? I guess there is suppose to be a hose back to the air intake tube. What is the point of the filter on top of the catch can?

 

[jetjock]

What I'd really like to see is JJ's opinion on this method as this is the first time I've heard of it done, this way (and that doesn't mean it's wrong by any means).

Interesting you'd say that because although he should lose the check valve depending on the amount of blowby he's closer to right than anyone else I've seen. That nobody else seems to have done it that way underscores my point about many people not understanding how the PCV system works in spite of it's simplicity. On the other end of the spectrum is Boostadikt's method. Worst thing that could be done. As hottscennessey points out the PCV system isn't there just for emissions. The reason I can tell you a lot about what happens in the accordion PCV line under different conditions is because I have a test port there to let me know when the air filter needs servicing. See attached photo.

The TB "boost leak" thing cracks me up. There's an orifice in there to limit flow ie; the path is nowhere near the size of the TB port. Plus the leak serves a purpose.

 

[IJ.]

 

[jetjock]

Lmao. As long as they put the crank at TDC on the compression stroke with the timing belt off they'll be OK

 

[turbogate]

Jetjock, what would you suggest for those with an FFI and Q45 TB ? I no longer have that stoc TB port for the vacuum. I have each valve cover going to 2 ports on the catch can, and a third catch can port to the turbo intake pipe, but like you said it is not good enough, my blown seals attest to that. What should I use to create positive ventilation?

 

[jetjock]

Sounds to me you may be using a can to compensate for a worn motor. Be sure blowby isn't excessive. That you blew seals is a sign of something more wrong than a lack of positive ventilation. Even then usually the dipstick will pop out before seals let go.

You can either duplicate the stock setup using an orifice to a vacuum source on the manifold or install a PCV valve like other cars have. That can be tricky though as PCV valves are not created equal. Whatever you do be sure you're using large enough plumbing. No tiny tubes. The stock setup is best as it provides air for dilution.

 

[starscream5000]

So it seems that we are getting closer and closer to finding out the best setup... Of course, the best one is to leave it like it came out of the factory (without getting too fancy), but let me see how this one sounds:

No check valves. Throttle body port straight to accordian hose. Ports on valve covers going into the catch can (with a baffle setup), then an outlet going to another port on the accordian hose ( I have a cooleeze accordian hose, so this isn't a problem for me).

 

[Sawbladz]

Damn...this is the third time I have tried to replay to this. Each time I forget to click ok to the old thread thing. Damn.

Oh well. Figured I would reply here instead of making a new one. This is my understanding of the PCV system and what my plans are for my catch can. Let me know what you think.

Stock:

Mine: