Relieving that crank pressure

[The Struggle]

So for my hot rod build I have been pondering some research on ridding my engine of blow by and crank pressures. From what I've seen people just weld in a vacuum to each valve cover and hook that to an electric vacuum source then through a oil seperator to catch the oil mist. Has anyone used this system or any ideas? I was thinking of running a vacuum line through the rear of my intake from the oil valley which would connect to the headers via a welded in tips in the exhaust stream to create a vacuum. It would pull more vacuum with more RPM (to an extent). The goal is to rid the engine of the blow by and oil mist so it will exchange oil better and keep them Molly piston rings sealed and lasting longer. Indeed I'll use a filter for each valve cover, separate of the vacuum line to draw in fresh air and use a small canister with steel wool to assist in collecting the oil mist which will be atop a vertical line to also help collect oil mist via gravity as well. If you guys could please give me any tips, pointers or bruises to my plan because I enjoy constructive criticism and thoughtful ideas.

Respectfully,

The Struggle

 

[da_raabi]

Doesn't a PCV system accomplish this?

 

[The Struggle]

Yes is does, but I have seen people say that these are only so good. To me it seems more beneficial to have a constant vacuum to pull the waste instead of a pressure control valve to need pressure to relieve the gases. My thought is the oil pressure will be the best thing to seal the rings and not having as much fuel mixed with the oil will keep performance up with friction and pressures down. But then again I don't know how much psi the pcv needs to open (need to do a vacuum test on my newer truck to see) but I also don't want a ton of vacuum drawn in the case either because that could just draw oil and gases through and away from the rings causing ring failure. My ultimate goal is 40 psi for oil and 0 crank case pressure so that rotating assembly is smoothly turned as possibly. What do you think?

 

[DoubleDingo]

I was considering something similar because I have an engine with the oil fill tube and the breather cap. The breather cap is spewing oil all over the place so that to me means there is a lot of pressure in the engine. I was thinking about running another tube from the driver's side to a tee that went to the breather fitting on the air cleaner. But I was also concerned about drawing too much oil through that and clogging the little filter element. So I am going to be watching this thread to see what others think on the subject. Although, I have seen setups where the breather hose from the valve cover wasn't connected to anything. I didn't like that idea because it could allow dirt to easily migrate into the engine.

 

[The Struggle]

I've seen people redirect the pvc and hose from the oil valley or at the valve cover/s right into the carb vacuum line or at the breather fitting. Great idea but I don't want oil back through my intake and on my cylinders and valves. That's why I'm amused at the idea of an exhaust vacuum drawn system. They use to do that back in the day or redirect the gases via a hose to atmospheric pressure with a variant vacuum like you can use in an exhaust pipe. That's why I like the exhaust type system, because as long as the engine is running the lines are under vacuum. I'll probably just build this system and run with it and see how well it performs. If i don't like it I can just plug it up with bolts in place of the parts. I'll be sure to build thread it because it saves engine and oil life alot and will cost less than $30 bucks to do.

 

[MadOgre]

I have a tube going from the valve cover to the inside of my air filter to access clean air.

I do not have any filter just pure open 3/4" hose and

I have good clean 3/8" tube for the PCV valve to the carb.

I do not have vacuum leaks or plugged filters which is the biggest source of poorly functioning PCV systems.

With the unrestricted tubing going to the air cleaner base there is very low restriction on the intake of fresh air into the crank case, allowing the vacuum on the PCV valve to do its job properly


I gotta say my crank case is squeaky clean too