Subaru Legacy 2001 non-turbo PCV vent to atmosphere

[bradlington]

Current:
Engine side: Airbox Side

Crankcase left===============(XXX)==Airfilter left side


PCV Valve =====================Top Engine
. "
. "
. "--------(YYY)-Small pipe to Arfilter box near center(My assumption is PCV failover protection)


Crankcase Right=============(ZZZ)=== Airfilter Right Side
.................................................. .................................................. ....
New :
Engine side: Airbox Removed
Crankcase left===============Breather filter left


PCV Valve =====================Top Engine
."
. "
. "---------Use for injection of Water or fuel vapor or HHO


Crankcase Right=============Breather filter Right

[bradlington]

I hope the old style of drawing line diagram represents what mu intentions are .

Once I have this I can remove the whole airbox and only use the Cargo large Cone direct onto throttle body.Previous placement of the cone filter directly on throttle body resulted in some additional noise when sudden acceleration - sucking sound - but plan to place a metal shield over it to make use of majority of air to be pulled in from hot engine .

The "failover protection " PCV connection , which has lower vacuum than the main PCV (a proportional relationship to main pcv flow) can then be used for whatever combination I want to inject be it HHO-water Fuel vapor , mist or perhaps all of the mentioned .
Once my new exhaust is on next week and the wideband AFR meter installed I would be able then have a good way of accounting for various changes being made .

One up on the Subaru design - I see many other makes of vehicles do not have this PCV failover design .

[bradlington]

Updated: Had my old exhaust replaced with 50mm stainless steel with one small Cowley box mid way and One Cowley straight through muffler .
Sound is awesome - like my previous impreza.Only catch is the fitment center did not have the tools to remove the front CAT and re-fit the O2 sensor-- I think I scared the hell oout of the service manager when I requested the additional wideband bung to be mounted between 10 and 30 degree max from vertical.
Today I went to see a well known performance specialist, whom builds and races vehicles and I saw some of his welding work - really precision stuff.Tomorrow I have my vehicle booked in and the necessary small 50mm bend has been acquired to replace the front cat . This should end my exhaust and next phase would be wiring up the wideband cables and gauge to monitor for a few days before venturing into next phase.

[bradlington]

I have just been re-reading over the older posts fom Aaron Murukami where he modified his Subaru PCV and he indeed blocked his actual PCV - allowed the back up - failover (my assumption )to vent from airbox. .The question would be , will have to place a vacuum guage on these three pipes to and from motor to see if there is any pos pressure inherently - if not how would the system work if there is no high pressure on one side of the system and no low pressure - this would mean gases would not flow .
Going to have to ponder over this one again .

[cRiPpLe_rOoStEr]

I wouldn't expect it to become an issue. Remember the Citroën 2CV? It generated vacuum inside the crankcase while the engine was running. OK, I know it's a whole different animal, but some vacuum might not harm efficiency at all. Maybe decreasing resistence against the turns of the crankshaft would even become somewhat beneficial. Not sure on that though, but seems worth trying.

[me and my metro]

On our race engines we would just provide enough vent area, no pcv. The engine was run wide open then closed throttle into the corners then back to wide open lap after lap. If you are going to run your car this way don’t bother with a pcv they only work at cruise and idle. Boats don’t have pcv valves they just vent both valve covers.

[bradlington]

Thank you for the information .Last night I had a brief search for Subaru EJ series being used in the aeronautical side.
I drive slower than my mother-in-law(so the reports from my boys are given as ) and certainly no speedster .
I am sure they do not use PCV or vent to air but if anyone has more ideas or references I would appreciate it .
Update - just returned from a motor rading expert and had the CAT deleted with two bungs - one for narrow band original O2 and a second one for my AFR WBO2 sensor - hopefully by weekend I will have the gauge in and can satrt taking more notes with each change.

[hayden55]

I second the exhaust connected pcv system. For road coursing mustangs which stay in gear under decel at up to 8000 rpm on the new 2011+ 5.0 motors (modified intake and operating range) the best way to keep a vaccum on the heads for good oiling and not drink oil is to connect up a exhaust manifold connected pcv system and its really low maintenance since there is no emptying of the can. Also, another good option os the old turbo volvo catch cans. The turbo volvo catch cans are baffled and allow the engine oil to settle at the bottom and have a return line at the bottom which is connected to a return line to the oil pan. Typically venting to atmosphere is a no no unless you're not worried about engine longevity or are not worried about catch can maintenance.

[ThermionicScott]

So this is the "Success Stories" subforum. What have you accomplished that you're bragging about, @bradlington?