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Discussion Starter #1
I am in the process of a engine build and all around upgrade of my Deuce over this winter and I am trying to come up with (without much success) what would be the ideal setup for the PCV system based around my power goal of 500whp. My 2 has a Gen2 engine and I do plan on running E85. With that in mind and from the info I gathered, in my eyes I am picturing a system vented to atmo with a drain back to the pan possibly through something like the Radium AOS and ideally there would be a vacuum pump to help draw the ethanol vapors out and provide vacuum when needed. I am upgrading the pcv outlet to a -10an already. Would a second line added to the other side of the valve cover help with pressure? Also would a second catch can help the system work better or instead of something like the Radium AOS use a bigger can with bigger or more filters? Im really up in the air on this so please if you have experience with how you handled or recommend to handle this setup im all ears. Thanks much.
 

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I'm pushing 325whp with an ultimate goal of 400. I'm using the single 5/8 inch PVC into a sealed catch-can, then routed to the pre-turbo intake pipe for a small vacuum. This has worked well for me.

I have seen two PCV hoses on valve cover before. I'm not sure it is necessary.
 

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All performance engines produce crankcase pressure and this is normal. Size of the engine is also a factor. On all of my V-8's we would use a venturi in the exhaust to draw out the pressure. This works on a V-8 because the exhaust pulses will create a steady vacuum. On all my small engines I just use a catch can in between the intake manifold and the valve cover with a one way check valve. A true vacuum pump would be total overkill for this small of an engine. The way really big power small engines do it is by using a dry sump system.

I have messed with this quite a bit and adding the pump to the pulley system would be fairly hard. Back in the 90's I used an electric smog pump off a 93 LT1 Camaro. It worked ok but I would not call it spectacular by any means. It definitely did not make any more power like a mechanical one would but it seemed to keep the valve covers cleaner. If it really bothers you it may be worth a try.
 

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I have 400whp and removed the pcv valve on the gen3 for two -10, then only to a vented catch can. I have a lot of oil mist now out of the back of the engine lid after 2-3 seasons of driving. If I did it again I wouldnt vent the can and instead would install a pan evac valve in the downpipe to help with ring seal.
 

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There are people who have tried that in the downpipe and like I explained above it would not be really effective as four cylinders exhaust pulses are not able to maintain a sufficient vacuum. On a V-8 application it works as you have the evac tube in the exhaust collector which receives four different pules as the engine is running.

I have a catch can not vented on my 4ag that goes strait from the valve cover to the intake and it does a really good job providing the pan evac without contaminating the intake charge with oil.
 

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Discussion Starter #6
Yeah it seemed like adding a vacuum pump would be a real task to get working properly in my opinion. While I really do like the idea of having the vacuum draw from the intake and running a closed system, my tuner thinks being vented to atmo will be needed for the pressures I will be seeing plus the benefit of not having that recirc lower my octane amongst other things. It seems to be a trade off of sorts with each setup having their own positives and negatives. Im just trying to see what others have found to work well for our engines within a similar power range so I can get it right the first time. Thanks for all the input so far.
 
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