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Aaron. Yes, I believe that is the correct hose. I've been thinking about doing the same. This one is a bit pricey, but I like that it offers 3/4" hose barbs. http://www.42draftdesigns.com/Ultima...Can_p_288.html
Have you chosen a catch can yet?
Last edited by Doug996InKC; Mar 24, 2015 at 09:07 AM.
Reason: correction: 3/4" hose barbs, not 3/8"
I plan on putting it inline as there is enough clearance and access to empty it -- without being near the pulleys, etc.
Some of the huge cans seem way over engineered. This may be too small, and if so I'll upgrade to a larger one. But I think it will be fine if I check it on a regular basis and empty it.
Really to understand the point, you have to also understand the history. Back in the day of motorcars, we didn't care much about the environment. We burned gas like it was free, let oil leak as it felt, and generally designed engines for maximum horsepower and torque without regard to other design considerations.
Today, things are obviously different and car manufacturers have a tons of regulations to worry about with regards to our environment. This is all good, but sometimes these two requirements go against each other -- performance motorsports and environmental design needs.
One of those design needs was to ensure we didn't have oil leaks. In modern high compression engines (also for the best economical and overall performance) you end up with positive crankcase pressure. This pressure has to go somewhere or things go boom... however, with this pressure comes all the things in a motor you would expect to follow -- mainly oil.
As I said, designers are not allowed to have oil go on the ground at all. So, they decided lets recirculate this into the intake. The assumption is that it will be very little and it will burn off in the combustion process and be further cleaned in the exhaust system. This meets the environmental needs and so is the way engines are now built.
However, for us that drive performance cars and drive them a little harder than your average grandma out there, we have a little more pressure in our motors than most. So, sometimes we have a little more oil than most. In fact, that is why you see some cars smoke for a little while after a hard driving adventure...
This oil is actually not good for your engine, it never has been. Your intake and combustion chambers should be clean and free of nothing else than nice cool and clean combustion fuels.
Hence we have oil catch cans.
Oil catch cans are an attempt to over come this design "flaw" in the interests of having our motors run clean of oil. It basically bypasses the environmental considerations in the engine design as you need to empty this catch can and do.... well... whatever you want with the oil I guess. In essence, it is being distributed into the environment like it used to in the old days.
Now to your question... sure there is a benefit to a stock motor, but I am not about to sit here and claim a longer engine life, higher performance, or anything else.
Why we supercharger folks are concerned about it is that adding forced induction to a naturally aspirated engine design increases the positive crankcase pressure more than it was originally designed for. If you keep your boost in check, that is fine, but it will cause more oil to end up in the intake manifold -- read: bad.
So, we are more keen to put an oil catch can on our cars.
I would still like someone to answer my original question about air flow direction being accurate. However, I pressed forth assuming it was correct -- it is an easy change if I need to swap the direction.
Anyways, this is how I netted out... it tucks in there nice, easy to see the levels and empty, and it all fits when the oil filler is put into place to clear the fan on the decklid.
Yes your explanation is good, I guess my real question is better stated like this;
I was under the impression the AOS basically did this, so would using a catch can be of any benefit ie like a redundant system?
To avoid the theoretical and move to the practical, this is what I would do.
Pick up some thread lock and electric throttle body cleaner. Take your throttle body off and do an inspection of the throttle body itself and the intake manifold area. Do you see brown deposits (aka semi-burn or old oil)? Can you feel oil when you rub a clean cloth inside the intake ports (in the low spots where it pools)? If so, your AOS is not keeping up.
This leaves you with one of two things -- bad AOS, just the way the engine works, or your driving is beyond the limits of the AOS.
In any case, clean that throttle body up and make it nice and sparkly. Be careful when you move the butterfly as you are not supposed to manually push it too far or put too much force on it. Give the intake manifold a nice wipe down with a lint free cloth -- or some high quality mechanic wipes. All this should be done anyways as it helps in the response of the throttle body -- not being all sticky and dirty with oil.
If it was clean as a whistle, you made it cleaner and you can rest easy without the need of a catch can. If it was a little bit dirty, perhaps the catch can makes sense for you. If it was an Exxon nightmare, perhaps you should also be considering an AOS replacement in your future.
To the last point, I did the AOS myself with the motor in the car. It can be done, but it isn't the most enjoyable job...
Hope that helps...
PS if anyone would still like to answer my air flow direction question that started the thread, that would be swell.
PS if anyone would still like to answer my air flow direction question that started the thread, that would be swell.
I'm no expert, but here's my take:
Your first photo, with the red arrow, is correct. The SC is creating a vacuum, thus "pulling" air from anything in front of it. To prove this is working correctly, referencing the photo in post #7, remove the left side of your catch-can hose, put your finger on the catch-can barb. Do you feel a little tug? Can feel anything? Light a piece of paper, or something similiar, hold it in front of the catch-can barb opening, and see if the smoke is "pulled" into the catch-can.
Air flow direction is: from filter > to SC > to intercooler > to throttle-body
Yes, same analysis I had based on air flow. The main air flow will cause a vacuum effect as well so it is just the logical direction. Also if you look at the stock configuration, that is the return line to the throttle body, so it all makes logical sense.
I'm just one of those guys that confirms things twice.
