UCM did help a lot. Thanks.

 

I plan on running one at some point soon. Just haven't had time to get one let alone do the install.

 

I was thinking about doing a catch can setup after I put the supercharger on

 

CompectTL....the reason why people dont do the catch can is because they dont understand the PCV valve completely....

this was explained to me by KN (Kurt) recently....

you have too much to account for....the front cover has the PCV and throws oil/vapors in the intake which are sucked by the vac in the manifold.... so you will have a catch can here....

the rear now only sucks fresh air and hence people put a filter there but it also has blowby, so you technically need a valve or another catch there....

the custom oil catch can which I got from Libert (Bert) recently kinda serves both the things....

I am putting it up for sale since I need some $$$ for another project....here are the pics for someone interested in making one for themselves or someone interested in these....powdercoated blue valve covers with 10AN fittings...












Done, done and Done

 

The right there is the correct way to do it! I have always ran a vented catch can to allow of fresh air to be pulled into the system as well.

 

Does anyone know the diameter of the hose. Is it 3/8 or 1/2?

 

Think its a 3/8 hose...half seems a little too big for the coolant bypass...

I get home today...will check for ya and update in here

 

Thanks. I know you texted me 3/8 but you weren't certain.

 

I am still not certain...will post up something tomorrow

 

I know this is old but I think it's important to remind everyone of the flow path and that it changes from normal driving to full throttle. From idle to heavy throttle, fresh air enters the rear valvecover. This air is filtered whether it comes after the factory air cleaner as the factory did it or with a little KN filter on the valve cover. This air flows through the crank case and picks up blowby gasses on it's way to the PCV valve on the other valve cover. The PCV valve is under vacuum from the intake manifold so it pulls air through the crank case in the right direction. From there it mixes with the other air in the intake manifold and is burned.

Under very heavy to full throttle, intake manifold vacuum disappears. Now you have no established flow path. In this case, the fresh air side is probably going to offer the path of least resistance for the increasingly large volume of blowby from heavy throttle. Instead of the fresh air side being an inlet, it becomes an outlet, flow is reversed.

If you have the stock config, the blowby now goes through the throttlebody to be burned. If you are aftermarket and have a little filter on the end of the fresh air, it can be vented to atmosphere (not legally). There's little to no reason to have a catch can here unless you have a turbo car and spend a lot of time with zero manifold vacuum. Otherwise, for 99% of your driving, fresh air and blow by goes in from the fresh air and out to be burned through the PCV.

On turbo cars it's very important to ensure no boost gets past the PCV valve. Many times it means adding an additional check valve. If you have boost pressurizing the crank case you're going to have oil leaks and a bad ring seal among other problems such as puking oil out of the fresh air side.

About the hose diameter, if you're adding a bunch of length it's a good idea to increase diameter too. Once my car starts leaking oil, especially from the main seals, I'm going to play with altering the PCV system to stop or slow the oil leaks. I've done it in the past with success. Basically it's increasing the PCV volume while restricting the fresh air side to lower crank case pressure or even to put it on a vacuum. Most would be amazed at how easy it is to slow and almost stop a dynamic seal leak by doing this.

 

^^^ Matt, Chris was asking about the Coolant bypass hose


but great explanation

 

lol. That's I get for posting while asleep. I saw one sentence and I read the title but apparently did not comprehend it. I literally fell asleep 4-5 times while writing it. I've got to get some sleep. I did a first for me today, fell asleep while standing at the urinal and almost fell into the wall/urinal. I think I know what I'll be doing at lunch. Thanks.

 

LOL...dont apologize brotha....you posted very well even in your sleep....

if anyone needs to know how the PCV works and why we only need one catch can, they should read your post