Negative Crankcase Pressure Setups

[tbauer03]

On my old set up I never got it set up to draw a vacuum to the crankcase under boost because I just had a filter directly on the turbo as a temporary solution that went beyond temporary. The stock setup is a very nice set up that makes good use of vacuum and the the PCV's but I was trying to get other ideas to potentially allow me to keep the filter right on the turbo.

Has anyone ran a vacuum pump on a street/strip motor or done anything different than pulling a vacuum from the intake system before the compressor wheel? Care to share pics?

Also has anyone had experience with MeWagners adjustable PCV setup?

 

[Don W.]

Re: Negative Crankcase Pressure Setups

What I did was drill hole in the air filter housing that accepts the hose from the second (under boost) PVC. Seems to work great.

 

[anryo]

Re: Negative Crankcase Pressure Setups

Also has anyone had experience with MeWagners adjustable PCV setup?

I read the instructions and seems, that it can't be used during boost, like we want to.

 

[Aeroking]

Re: Negative Crankcase Pressure Setups

C5 corvette used an electric vacuum pump that is pretty compact. I have 2 sitting in my garage. Let me know if you want one.

 

[anryo]

Re: Negative Crankcase Pressure Setups

C5 corvette used an electric vacuum pump that is pretty compact. I have 2 sitting in my garage. Let me know if you want one.

Is it a "vacuum" pump, or is it really capable of pumping gases out? The somg pump 'vettes have, is for pumping the air IN, I have understood?

 

[tbauer03]

Re: Negative Crankcase Pressure Setups

I have read bad things about electric pumps reliability and pulley driven pumps seem to be for race only motors. Has anyone gone either of these directions and care to comment?
Don I like your idea I might be able to make that work using a 90 degree fitting. Thanks for sharing that.

 

[Peter]

Re: Negative Crankcase Pressure Setups

What Don describes worked great for me also. I used a barbed elbow from McMaster-Carr part 91355k24. The 3/4" barb goes into the valve cover and 1/2" barb for the hose. Then McMaster-Carr 91355k46 1/2" barbed elbow to go into a tight hole in the rubber end of the air filter. For hose, McMaster-Carr 5633k24, oil resistant and not so heavy as some other hoses. Of course the other rocker cover has the PCV valve and connects directly to the throttle body. The whole system is clean and simple.

 

[Don W.]

Re: Negative Crankcase Pressure Setups

You can't see it in the pic but that hose goes to the stock PCV setup. Only thing different is I ran the hose to a different location. My thought was the stock setup is never gonna see much vac (under boost) and neither will mine... It seems to work to the extent that I don't much, if any, oil around the breather on the drivers side.

 

[anryo]

Re: Negative Crankcase Pressure Setups

BTW. I have tried many other "non ACDelco" valves available, but they all bleed through on boost. Does the OEM CV779C valve is completely shut on boost, so no boost can pass to crankcase?

 

[Peter]

Re: Negative Crankcase Pressure Setups

When I blow into the OEM PCV valve, it does seem to close completely. Before the latest set up, as described earlier, some oil mist came out of the breather filter I had on the driver's side, presumably from cylinder blow-by under boost. Passenger side was basically the OEM setup. The passenger side now is just an open 1/2" hose to the air filter. The driver side now has the PCV valve and goes to the TB. This is a little different than Don's, but seems to work. Now, everything is bone dry.