PCV/Catch Can Dilemma

[2010BlackCamaroSS]

When my car was in the shop for a cam install, I misunderstood what the shop was asking me when they were installing the catch can and ended up with a vented setup and no PCV. There is a hose coming from each valve cover into a vented Mighty Mouse catch can. The vacuum port on the intake manifold is capped as well as the fresh air port on the air intake tube. There is no fresh air being pulled in to evacuate the crank case.



My dilemma is that neither the vented setup, nor a PCV setup, seem optimal. I have done a lot of reading about PCV vs. vented, and 98% of what I have read tells me that running a vented setup is not good for the longevity of the engine. However, the shop seemed to favor the vented setup over the traditional PCV setup. I feel like they know these engines very well, so maybe the detriments to an engine with a vented setup is not a big deal? If vented is so bad, I feel like they would've advised against it.



Below are some pros and cons of each setup. If I am off base here, feel free to educate me.



Vented Setup:

PRO: Keeps hot, contaminated air from being introduced into the intake manifold, improving performance.


CON: Contaminants build up in the crank case and pollute the oil, reducing oil life and negatively affecting engine longevity.




PCV Setup:

PRO: Evacuates contaminants from the crank case, extending oil and engine life.



CON: Introduces hot, contaminated air into the intake manifold, reducing performance.




While I realize that a good catch can reduces the amount of oil vapors and contaminants being introduced into the intake manifold, it can't filter out everything. Also, the air coming from the crank case is hot; so even if the catch can could filter out all contaminants, theoretically, the hot air would still reduce power/performance, right?



Performance is a big deal to me, so I hate to sacrifice performance if I don't need to. In fact, the power I gained after the cam swap is the only reason I changed my mind about selling the car. I hated this car after I had it awhile and realized how slow it was. I loved the look, but hated the performance.


Anyway, I am looking for some guidance here. I am trying to choose the lesser of the 2 evils. Should I leave it vented or return it to PCV? Please back up your vote with reasons why.


Thanks all.

[Pkeen]

I run mine vented ,no way I'm running oil and crap back into my engine. I've always gone this route on my engines and never had any issues with it. There will be others in here that will tell you the opposite. Each to his own.

[Eddymel1998]

From my understanding venting introduces an unknown variable into the system that otherwise is sealed and controlled, with hot air introduced into the intake I can't really imagine it's enough to make any noticable changes if any.

[xstuntman]

From what I've read the PCV extends the life of an engine compared to pre PCV engines back in the day. Must be some nasty gasses brewing in that bottom end.

[Badbubba]

I run a Rx, closed loop, catch can. Did the shop block off the fresh air feed from the intake tube? The hose is only about 1/4", so it's not going to have a large volume of hot air. Besides, the air cools somewhat before it gets to the intake in the hoses and can. You can use a check valved breather for the oil filler. Relieves excessive crank case pressure by venting. Otherwise, the pcv acts as a sealed system.

[morepowerjoe]

Ok buddy, let me see if I can help you. I've read a lot about pcv systems, and from what I can tell you like someone else said earlier it depends on who you ask. I do know if you ask a big name person about it they will say go vented but those guys are really just talking about a full blown max effort race style pcv. They don't really know much about a daily driven vehicle that sees all the temperature fluctuations and demands of a daily driven vehicle. I personally would definitely would recommend a pcv system over a vented style any day over a vented style system for a couple reasons. First of all it, there is now way you could ever pass an emissions test without a pcv system because your letting all those unburned gases released into the atmosphere which isn't very environmentally friendly. Second, your not pulling those gases from you engine so your eventually going to have sludge build up in your engine because of all the vapors just sitting in your engine not really going anywhere and a vented set up doesn't pull the gases out like a pcv system which can be reburned caused by blow by.

So which one should you use? I personally like the Mishimoto one https://www.mishimoto.com/chevrolet-...2010-2015.html mainly because of the cool mounting location and the compact design of it. I don't think you need a giant can like some of them out there not unless your just the lazy type that only wants to dump his catch can like every six months. It's a dual port design that just has a in and out which is all you need. To hook up a pcv the correct way all you need to do is pull it from the drivers side valve cover into the catch can and out to the intake manifold and then connect the passenger side valve cover to the fresh air inlet on you intake tube. And pretty much any catch can will work you just have things like baffled and non baffled, and two port versus the three port (which I'm not a fan of) that hook up a little differently.

One thing that a lot of people don't know about is the tuning though. If they tuned your car with the vented style catch can it could possibly change your idle a little bit. You might not even notice it and if you don't I wouldn't worry about it but if you experience any idle problems then You will probably have to adjust you base running airflow in your tune which is very simple.

Other then that I think I would swap to a true pcv system and you won't even notice and performance issues what so ever.

[larry_g]

Get in touch with mighty mouse, I don't believe that is how his catch cans are designed to work.

From your description, there is no controlled flow of crankcase gasses to the can. His vent to atmosphere in an overpressure situation but you still need to pull vacuum to help evacuate and catch contaminants in the can.

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[Moto-Mojo]

Maybe I'm missing something in the details. Does not say, an Elite catch can, simply mount in-line where the stock PCV tube ran? I do have a fresh air source coming from the GM CAI but the can is simply in line. No other connections. Is this a "correct" arrangement?

[Moto-Mojo]

I do understand what the OP is saying about driving an older Camaro and growing a little bored with the performance aspect. Still mostly enough for me but it seems most things that want to run me at a light, beat me. An 8 year old, 400HP L99 Camaro is becoming a bottom feeder on the modern performance scale.

But maybe I'll beat them in the Reliability Dept!

[morepowerjoe]

Originally Posted by Moto-Mojo

Maybe I'm missing something in the details. Does not say, an Elite catch can, simply mount in-line where the stock PCV tube ran? I do have a fresh air source coming from the GM CAI but the can is simply in line. No other connections. Is this a "correct" arrangement?

Yes that is all that's needed is to run it inline where the stock pcv is and a fresh air unlet from the passenger side valve cover.

[Moto-Mojo]

Originally Posted by morepowerjoe

Yes that is all that's needed is to run it inline where the stock pcv is and a fresh air unlet from the passenger side valve cover.

Thanks! I didn't think it was rocket surgery.

[FasNuf]

I run a Mighty Mouse catch can and the filter breather on top only vents under boost. When the catch can is under vacuum and vacating the crankcase, the flapper valve in the breather closes. It's meant to help the crankcase get rid of any blowby pressure during boost. If your MM can has both hoses going to valve covers, it might be hooked up wrong.
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[JAFWF]

Instead of me prattling on, I am going to let you read what the manufacturer has to say about their dual exit port can. Also not going to be involved with the bigger can versus a little bitty can, will let Elite handle that as well.
They also have a very informative install video that walks you right through the install.




The E2-XTM Dual outlet system


https://www.eliteengineeringusa.com/e2-x-catch-cans/

[olblue75]

Take a look at these; https://youtu.be/ktXj_-FN9rE