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Yoshifab Catch Can or Provent Feedback?

Well the heater element on the intake hose should prevent the ice if it's hooked up ;-)

You planning on having the provent drain back to the block anywhere? I'm debating just putting barbed fitting on the drain side of the stock breather and draining into there, don't see why that wouldn't work.

Same thing I was thinking, but with a YoshiFab kit on the way for my wagon maybe not. I like that the Provent is 1".

I guess I will get one of these for my other cars.
 
I used Provent on VW pancake motor. It's a good part for the money.

On the related subject: draining oil back into the crankcase from the catch can should be avoided whenever possible.
 
Because other than perfectly good reusable oil the can will contain water condensation, fuel and blow by contaminants mixed with it. Think of an oil catch can as filter- whatever it caught doesn't need to go back.
 
Because other than perfectly good reusable oil the can will contain water condensation, fuel and blow by contaminants mixed with it. Think of an oil catch can as filter- whatever it caught doesn't need to go back.

You might want to have a chat with every engine manufacturer out there. The stock oil separator drains back to the crankcase. The provent is just doing a better job of separating the oil from the blowby gases. There's no functional reason not to drain it back. You should be getting your oil up to temp so the water vapor and other volatiles will evaporate.
 
Depends a lot on the can's location I guess. In some the water will condense and turn into something like this:

PCV_residue.jpg


Once you've looked into a catch can or two that don't drain back you have your mind all made up. But it's not super critical or anything- not like you are gonna throw a rod because of this.
I am sure that chatting with every engine manufacturer will make me smarter but who has time for that:)
 
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Because other than perfectly good reusable oil the can will contain water condensation, fuel and blow by contaminants mixed with it. Think of an oil catch can as filter- whatever it caught doesn't need to go back.
That's why your factory separator box is built into the block and made of plastic - to stay hot and to avoid the possibility of water vapour condensing out, instead letting the intake breath it out.

Factory ones are never (that I've seen) mounted far away, and in some cases are internal to the cam cover for max heat.

If you're building something to act as a dehumidifier, then sure, draining milk and cookies back into the sump is pretty ugly, but be aware that that's a scenario you've created that didn't exist in the (pretty damn good!) stock setup.
 
Of course. And temperature of the air/oil separator affects how much oil is caught as droplets on the internal walls and how much will pass as vapor.
In this thread we are talking about add-ons that probably any manufacturer would say are not necessary if I had a chat with them.

Very cool read with illustrations on how the catch cans work and what works best. I recommend: http://file.scirp.org/pdf/JTTs_2015102713561990.pdf
 
White block pcv is usually clogged around 100k with factory 7500 interval... I work at a dealership so I see everything from perfect maintenance to not so perfect... either way if you made it to 100k without replacing pcv you did good. Driving habits definitely affect it also.


I'm starting down the pcv road on my race b230 and I'm looking into options that don't put vapor back into intake side. I'd like to be able to drain the water since e85 might be in my future. No inspection here in NJ for -96 So as long as scca tech is happy I'm happy.
 
I ran e85 for the last 4+ years. When I had an external catch can that did not have the turbo draw a vacuum on it my catch can was always full of nasty sludge that would fill up in less than 2000 miles. Sure my rings were beat to hell but it was still 350+whp. When I went to the yoshifab setup I not only drained it back to the block but I also put a vacuum on it pre turbo, the hoses going to the return to the block we're nice and clean layer of oil with no signs of water contamination and the preturbo hose had little to no oil in it.
 
No inspection here in NJ for -96 So as long as scca tech is happy I'm happy.

Not sure about NJ but in very strict CA they are legal for the most part and do not require CARB approval number. As long as they are not open to outside air (have breather on top) and factory PCV system is still the same configuration- you are OK to have them.
When using extra hose to connect it has to be Emissions approved though- heater hose is never OK on PCV.
 
My brother just built a fresh 1.8t vw race motor for his Audi TT making 550+awd hp. He runs e85 cuz he's pushing 40 psi at times. Catch can gets full quick. He does occasional drag racing (125mph+ trap speed) and always kicks my ass in autocross.

After every track day catch can is full. I'm not sure how much of the stock pcv system is still there. Runs amsoil everywhere possible and changes it very often. Maybe its overkill but I damn sure would rather be able to remove the sludge manually rather than rely on the stock setup (on a not stock motor) to boil the water away. I've seen the sludge and it's not pretty. Reminds me of taco Tuesday with a touch of dysentery...

The stock/junkyard NA motor In my 76 240 scca car has a stock short breather box with a little filter atop of it... it tends to belch a bit considering the abuse I put it thru. I run castrol 5-20 full syn ( cuz it's free) currently. Once my stroker b230 is running I'll be on amsoil also. Thanks for the input guys. I'll be keeping an eye on this thread...

Also as I said my car is a track car that sees limited street use with no state inspection. Only rule book I'm looking to comply with is whatever sanctioning body (scca, NASA , msne) puts out. And they all say no leaks... so i need to remedy things...
 
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White block pcv is usually clogged around 100k with factory 7500 interval... I work at a dealership so I see everything from perfect maintenance to not so perfect... either way if you made it to 100k without replacing pcv you did good. Driving habits definitely affect it also.


I'm starting down the pcv road on my race b230 and I'm looking into options that don't put vapor back into intake side. I'd like to be able to drain the water since e85 might be in my future. No inspection here in NJ for -96 So as long as scca tech is happy I'm happy.
Not 100% sure about white blocks, but redblocks DO NOT RUN PCV, they run CV, only. There is nothing positive about it, whatsoever. PCV is defined by reversible flow, under high power it comes out the free vent on its own accord, under vacuum it's drawn through the engine (clean air goes IN) and out into the manifold at a controlled rate thereby purging the bad gasses and replacing them with the usual breathable mix.

Volvo doesn't do that.

Volvo redblocks (at least, and I thought white too, but...) merely vent any excess volume out the large factory oil-air-separator to alleviate leak-causing pressure build up. They do not controllably, or otherwise, vent clean air in while those gases are flowing out, at any manifold condition.

That's why PCV is superior, though I appreciate the simplicity of the Volvo setup, myself (at least, when it's clean! which as alluded to, is not for long due to a lack of fresh air).

In any case, I object (strongly) to using the term PCV to refer to the redblock system (at least), as it's just plain wrong.
 
You might want to have a chat with every engine manufacturer out there. The stock oil separator drains back to the crankcase. The provent is just doing a better job of separating the oil from the blowby gases. There's no functional reason not to drain it back. You should be getting your oil up to temp so the water vapor and other volatiles will evaporate.

+1

Oil gets hot, contaminants burn off.
 
Not to stoke the fire, but where does that burned off condensation go? Back out the pcv and into the catch can? Then back into the oil pan? HOW DOES IT LEAVE :O
 
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Get the oil out of the vapors and burn the vapors off in the combustion cycle.

The major purpose of the catch can (aka oil separator) is to return the vaporized oil back to the sump and let the rest of the blow by vapors escape either by venting to atmosphere or via the intake plumbing.
 
If one is willing to periodically check and drain the can of whatever was unlucky to get trapped there and replenish the oil level then do so- you are doing your engine a small favor.

Adding this as maintenance point to regular production cars driven by regular people who do not take pleasure in opening their car's hood was obviously not necessary- no arguing about that.
 
If you want to do your engine a big favour you put a vacuum pump on it and put a small leak somewhere opposite that so that it's constantly flushed out and bone dry - bonus, more power.

You're engineering the favour in your head because you remote mount and get cold gooey goodness in there. It never even forms in the first place in the stock arrangement. The oil goes down and the water vapour and CO2 go out as generated, only the residual is left, and that's unchanged with your scheme, residual is still left. No favours done, whatsoever. Seriously. :-D

Maybe you have bad rings? No separator/can can help with that.
 
Thanks, but I personally don't run a catch can- all stock for now.
Good point about cold gooey goodness not forming in stock location- right on the block is the best spot for evaporating that. But I thought the subject here is not how great the factory engine venting system works.
There are some cans on the market (not ProVent or Yoshifab) that are super proper about keeping hot while mounted remotely from the block- they have engine coolant running through them.
 
Link? That's not a bad idea, but smells of unneeded complexity to me, when a simple system that's well designed will do the job perfectly well. Still, worth having the option in the back of the mind in case it's needed at some point.

Data point: My truck, 2.0l, 8000 RPM, 18psi, ~400hp @ crank (+/- 50 depending on who you ask and/or state of tune/fuel/etc), 2 to 3 times factory output level, NO catch cans/separators, two fittings/hoses with about 12mm ID (apologies for metric on TB) routed up at about 45 degrees for a few inches, then horizontally, then down to a coke bottle and methylated spirits bottle (LHS and RHS respectively). No oil or water or sludge or anything in there, because nothing comes out of the engine. It's moving slow enough that it collects inside the cam cover labyrinth and stays put. On the other side, without the labyrinth, same deal - not enough velocity to carry heavy oil droplets out of the engine up hill.

This is a PCV system, ie, clean in, dirty out, or dirty out both sides, depending on operation mode of the engine. On the right, the long chamber with many redirections inside and around 1/2" height inside is for the free vent to the inlet pre throttle/turbo. On the left is the chamber setup for the to-plenum valved side. And in the second photo is my additional passage out for greater flow at lesser velocity, only split by a vertical division that prevents the intake cam spraying oil into it.

Db3QqjMUwAAzwQ5.jpg


Db3QtoyU0AA5wnK.jpg
 
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