blow-by


Aug 25, 2006
4,436
In paul's setup - under vacuum the engine vents normally but filtered through the Provent. Under high engine loads, the PCV valve is closed and his added check valve to the driver's side PCV hose prevents normal engine ventilation via the front of the throttle blades. The side can only be used to suck air into the crankcase. This will cause the crankcase pressure to build up until the pressure relief valve in the Provent vents blow-by into the engine compartment. This sound like the best way to connect only one Provent. If you used 2 of them then you wouldn't have to vent into the engine bay.


Based on the understanding as shared you are correct; IMO there would only ever be a need (if at all) for one for the passnger side. If one is installed on the driver side with NO check valve one would be fine however I have never seen signs of oil being drawn through the TB

All the best with your prject

Shadowman
 

STORMCAT

GT
Mark IV Lifetime
Le Mans 2010 Supporter
May 25, 2006
7,572
Ft. Lauderdale
Could we get a Ross Perot chart or diagram of this? I'm confussed..:willy
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Stormcat read an earlier post on this thread. There is a link to a pdf file about the Provent device. It shows diagrams and options of how to hook it up.

All I know is anyone that has off the blower will clearly see the intercooler fins are covered with oil from the PCV system. I don't know for sure if this causes harm. The only useful thing I can see is the oil vapors may lubricate the blower's rotors increasing lifespan. The potential downside is the oil on the fins of the intercooler must diminish the heat transfer of the intercooler system.

Note, if you are going to filter out the oil from the blow-by, you should probably clean the intercool fins to get any benefits.
 
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Aug 25, 2006
4,436
Stormcat read an earlier post on this thread. There is a link to a pdf file about the Provent device. It shows diagrams and options of how to hook it up.

All I know is anyone that has off the blower will clearly see the intercooler fins are covered with oil from the PCV system. I don't know for sure if this causes harm. The only useful thing I can see is the oil vapors may lubricate the blower's rotors increasing lifespan. The potential downside is the oil on the fins of the intercooler must diminish the heat transfer of the intercooler system.

Note, if you are going to filter out the oil from the blow-by, you should probably clean the intercool fins to get any benefits.


There is absolutely no lubrication benefit derived as the result of the oil; only the messy film it produces which certainly can contribute to higher intercooler core temperatures. The only reason that it is feed this direction is because the system accoring to OBDII needs to be sealed.

Now with that havig been said I follow the statement with because Ford elected not to install a oil separator when in fact many other OEM's do.

So what is the best way; the best way IMO is the simple way which means to leave the system as it is (meaning the primary hose routing) and then simply add a oil separator let's say one neatly mounted to the right rear shock brace using the exiisting bolt through hole so in the end it would appear as OEM to all including the inspection stations in the future years. This area also offers the ability to install a large enough unit. Then route the line from the SC'er to the oil separator then from the separator to the OEM PCV valve with the drain some place in the lower block area (as also mentioned by paul b); now I have not looked but I suspect that as with most blocks there is a oil galley plug or ?? that can be used. Considerig that the gal is dry sumped the idea of going directly into the pan is likely not a great idea. Furthermore the idea of a drain back into the same valve cover that vacuum is being drawn from is also not a great idea.

Takes care

Shadowman
 
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paul b

GT Owner
Nov 2, 2006
810
Just to add to the pot, Vipers changed their valve cover venting from the rear to the front because of oil being forced to the rear of the engine during hard acceleration. Every little bit helps. Like was said before, looking at that intercooler for the first time is scary.
 

04CobraMatt

Member
Aug 28, 2007
5
Just to add to the pot, Vipers changed their valve cover venting from the rear to the front because of oil being forced to the rear of the engine during hard acceleration. Every little bit helps. Like was said before, looking at that intercooler for the first time is scary.

Intersting... just to add, any oil pulled from the PCV you DO NOT want to route it back to the oil pan or dry-sump. That oil is full of moisture and/or other contaminents that should be disposed of properly.


Shadowman, thanks for the explanation. I know people have gone to a dual-breather setup on Cobra's but iv'e never hard them talk about the neagtive of loosing vacuum in the crankcase.
 

Beach-GT

GT Owner
Mark II Lifetime
May 8, 2006
887
Seminole Florida
Seems like the aforementiond separator should just be added in the PCV line and the drain routed to a small bottle to collect the drippings for disposal. Where can I order one of these?
 

paul b

GT Owner
Nov 2, 2006
810
Seems like the aforementiond separator should just be added in the PCV line and the drain routed to a small bottle to collect the drippings for disposal. Where can I order one of these?

Go to post #5 of this thread, 928 specialists
 

Beach-GT

GT Owner
Mark II Lifetime
May 8, 2006
887
Seminole Florida
I ordered one from 928. This can't be that hard to install. :ack
 

paul b

GT Owner
Nov 2, 2006
810
getting the plumbing to look neat is the only problem. Pick your location and fabricate a bracket. Once you have the Provent in hand it all comes together, pretty straight forward.
 
Aug 25, 2006
4,436
Intersting... just to add, any oil pulled from the PCV you DO NOT want to route it back to the oil pan or dry-sump. That oil is full of moisture and/or other contaminents that should be disposed of properly.


Shadowman, thanks for the explanation. I know people have gone to a dual-breather setup on Cobra's but iv'e never hard them talk about the neagtive of loosing vacuum in the crankcase.


You are welcome

As for dual setups; one of my purposes was to share that IMO the there is no need for one on the driver side because of the air draw location and the fact that on any given day the bellow's can be removed with no signs of oil prior to the TB. Furthermore IMO I would always want a means for crankcase pressure to at least remain equal to the atmostphere considering that no vacuum is present when under boost so as to keep the seals and gaskets happy. This is why I made mentio of racer's using an isolated vacuum pump so they can control and maintain a vacuum at all times regardless of the gal's throttle/load position.

Now as for the concern for condensation; "IF" the gal is started and then fully warmed up this would be minimal at best and is a normal process of the distillation process that occurs everytime you start a car. There is far more moisture within the crancase after start up than you will even get through the PCV system. Then as the vehicle warms the modest amount of created moisture will dissipate however having shared this a catch can would work fine but will require some service and will "NOT" conform to the OBDII standards and the later was my greatest issue for those folks looking to maintain a compliant gal.

I am all about "Proof of Life" as such pictures are a great thing; please post some as your projects unfold.

All the best

Shadowman
 
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