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Blue Oval Man
12-10-2012, 08:46 AM
I am running a moroso catch can on my FE 68 Mustang. I have closed breathers on my valve covers with nipples with 3/8" id tubing going to the catch can that is mounted on the back of the engine behind the carb base. The catch can presently has a k&n style open element breather on the top.
Can I put a pcv valve on the catch can and go to the pcv port on the carb and have the system work properly?
Since the breather caps on the valve covers are closed and don't allow air into the engine, do I need to find a way to let air into, or vent, the engine, or is it OK to just let the pcv system suck air out of the engine?
I like the way my system is set up now because it looks neat and tidy and doesn't allow blowby all over the valve covers but I would like to use the pcv system to eliminate the oil smell that gets a bit much after some hard driving and to also help suck the gasses out of the engine also.
Has anyone used this pcv valve? Costs a bit more than a generic one but does the tuning aspect of it make any sense? www.mewagner.com (http://www.mewagner.com)
David.

Zee
12-23-2012, 07:31 AM
You can leave one side connected to your catch can with the breather. That will serve as an intake. The other side is going to have to go to PCV valve of some sort. If you installed the valve in the catch can, I can't see how it would evacuate the crankcase.

Blue Oval Man
12-26-2012, 10:43 AM
Maybe I am thinking about this all wrong but if the breather is on the catch can and the pcv valve is pulling a vacumn on the engine, how would the oil get to the catch can? Wouldn't the pcv vacumn keep any oil or gasses from getting to the catch can?
So if I was to mount the pcv valve in the breather location on the catch can going to the baseplate of the carb, and drill a hole and mount a fitting on the rear of my driver side valve cover with a hose going to the catch can from that side, and the hose from the passenger side also going to the catch can, I should be able to put a regular breather in the original front location on the drivers side valve cover. This should give an air intake into the engine and also allow the pcv valve to pull the gasses and oil out of both valve covers, separate the oil in the catch can, and pull the gasses back into the engine through the pcv valve. Maybe I am not understanding this right or trying to overengineer the whole system but I would like to keep the engine vented properly, keep the mess out of the engine bay and not be pulling harmfull oil back into the engine all at the same time, while looking good at the same time.
David.