Crankcase Ventilation

[Dwight Southerland]

Originally Posted by Wade_Owens

Brake booster valves are not created equal. There is dyno proven power here if you work for it.

Wade

As are PCV valves. . . . and you are very correct that you have to work for it.

[Frank Castros]

Wade,
Please expand on your comment of "releasing the vacuum for the oil to drain".

Originally Posted by Wade_Owens

I have tried several theories at the track and confirmed some of them on the dyno. Brake booster valves are not created equal. There is dyno proven power here if you work for it. Mine will suck the bottom of the pan up against the pickup. You have to "release" the vacuum for the oil to drain. Then you'll know your close!

Wade

[Bobby DiDomenico]

Originally Posted by eddie c

Yes, That was another trick,You were supposed to run the front crank seal backwards and also, if possible, turn around your rear main seal.
ed

Can you actually pull enough where the seals would become an air leak?
I was guessing this is mostly extra carburetor cfm, just not using hollow bolts n things.

[Wade_Owens]

Originally Posted by Frank Castros

Wade,
Please expand on your comment of "releasing the vacuum for the oil to drain".

Sure Frank, after the engine is warmed up, and I'm ready to change the oil, I have to "release" the vacuum that my system creates or the oil wont drain from the pain. The first time this happened, it scared the s&*^ out of me, I thought I had forgot to put enough or very much oil in it. After opening the filler spout, the oil drained freely as it had always done before.

Also, be very careful while playing with this, it does affect the oil pressure. If you use thin oil and low oil pressure, it messes with the bypass valve in the pump.

Wade

[Frank Castros]

Wade,
Thanks, that's a great story, and it seems that you have found the system that works for you.
This is a subject that merits serious consideration.

[Jeff Lee]

I've spent a lot of money on PCV valves; trying different applications that I wont go into detail on. But yes, some work, some work better than others..and some don't work.

[Ron Gusack]

Originally Posted by Tylerdax

i think your refering to a check valve that is screwed into your header.......brakebooster check valve is plastic and similar to a PCV valve in size

Yes, plastic valve that only allows air to travel in one direction. When manifold vacuum drops to zero, the header is supposed to take over. That's when the valve does not allow air from the intake to go out the header.

I've never run a PCV valve, just the sealed Moroso breathers. Does this setup appear wrong? How do I keep oil from being pulled into the intake?

[Pat Cook]

Originally Posted by Wade_Owens

Sure Frank, after the engine is warmed up, and I'm ready to change the oil, I have to "release" the vacuum that my system creates or the oil wont drain from the pain. The first time this happened, it scared the s&*^ out of me, I thought I had forgot to put enough or very much oil in it. After opening the filler spout, the oil drained freely as it had always done before.

Also, be very careful while playing with this, it does affect the oil pressure. If you use thin oil and low oil pressure, it messes with the bypass valve in the pump.

Wade

Wade have you ever connected a vacuum gauge to your crankcase?

not being a hydraulic engineer or anything like it, but don't pumps need a certain amount of atmosphere pressure to pump?

brake booster check valve and a sealed crankcase, sounds interesting. Use the manifold vacuum to pump the crankcase down.

[FED 387]

believe it or not if they are set up right ya can actually hear the air hissing a little(of course with the engine shut off) also pay close attn to any oil being sucked into the intake it will/could coat the top of the pistons and create detonation !!!

[SGSST109E]

Back in the 70's we ran the single ring pistons in modified eliminator. The key was to have the engine sealed. Not having access to a vacuum pump we would take the vacuum off the running tow car to test the engine seal. We would try to have in maintain vacuum for one min. Today they make double lip crank seals we used O rings back then in the front and rear seals. We always had vacuum gauges in the cars. The system we used was the moroso setup on both headers as well as one going to the intake under the carb. We used the same mopar check valve that was used on the headers. If the motor was sealed you had small traces of oil in the intake after a run. With the oil separtors available today that should know longer be and issue.