vacuum pump... could the AIR pump (or whatever that useless electronic thing is on the front) that's already on the engine be used as a vacuum pump? if it's not being used for anything else.

 

Yeah someone suggested that a long time ago. I have no room for the catch can and all related things to make it work. And I didn't think it would benefit enough to go through the trouble of setting it up.

 

I have the passenger side tube going from the valve cover to a little filter I made out of PVC - kind of like a little catch can with a drain plug and from there it goes to the intake before the blower inlet, but after the MAF. The PCV valve hose goes to a brake booster check valve and then to the front of the intake manifold as normal. The extra check valve helps under boost to not let the boost get by the PVC valve and pressurize the crankcase. I don't have a breather and no leaks or blowby. I just rebuilt the engine 200 miles ago.

Now with the old engine it was not set up that way. I had blowby and a couple little oil leaks - I had oil going in the blower inlet duct, too, and was spending a lot of time fussing with how to deal with it, but broken pistons was my real problem. But I had a breather, didn't have the extra check valve, and had the same line going to the homemade filter and blower inlet as I do now. None of it worked very well no matter what configuration I tried because how ya going to make up for all that compression in the crankcase. In the end it blew a head gasket at the track last fall and finally I HAD to rebuild it. It still went 12.0 - 117-119 mph on it's day on earth with broken lands and rings on#1 and broken lands on #7 and water leaking into the oil.

 

That's been tried, but they get contaminated from the oil in the air and die. I bought an extra one just for that reason and ended up not doing it after doing a lot of research. Mr. gasket advertised an electric vacuum pump in Car Craft, but then never released it due to problems. There was a guy that made a Gast 12V vacuum pump work with success, and I was going to try that too, but in the back of my mind I really knew I had piston issues. Now that I have the engine repaired, I have a different perspective on the subject.

 

interesting. I guess I don't understand how pressure builds in the crankcase.

I'm thinking about running both sides to a vented catch can. It would allow "breathing" and keep oil from going into the intake. Of course I would have to cap off the hole on the intake below the throttle body. Do you see any problems with doing that?

 

Pressure builds in the crankcase from blowby past the piston rings. PCV uses manifold vacuum to eliminate that pressure and any unburnt gasses.
The catch can idea is ok but why not hook it to the intake instead of venting to the atmosphere? The idea is to attach a vacuum source to the crankcase to make the whole thing work effectively. If you are worried about some oil entering the intake, use the catch can to filter it but keep the system functional.

 

What about a Crankcase Evacuation System. It would suck for all the environment , but it would suck for the engine as well ...as in getting all the crank case gases out and would not burn them in the engine . This would help the plugs and valves stay cleaner, plus it would not introduce heat and less than ideal gases to contaminate or dilute the incoming air/fuel mixture. Looks like it would be an ideal cure all for cars that are only drag raced. Please understand that I have not ever tried this setup so I do not even know if it would work. Thanks, Shimaze

 

OK so I think I'm starting to understand why some ddrag engines have a vacuum pump. Especially the boosted ones.

 

In addition to the above...On a blower car that retains the PCV system, the intake gets pressurized and tries to blow air past the PCV valve (which doesn't do too good of a job keeping it out) and into the crankcase so the extra check valve helps out there.

 

Those are no good on the street. Best left for a track car.

 

if breathers are so bad why did anyone ever make them? of are they just a problem with boosted motors?

 

They came into being before the advent of the PCV valve, when out of a tube in the back of the engine fumes were released into the air and oil dripped onto the road.

 

ah i see thanks. grr all the trouble i went through custom fitting my K&N breather too since my valve covers are aftermarket and the pcv hole is smaller.

okay on my s-trim i have the maf on the pressureside aka stock location. so the hose that goes to the passenger side valve cover needs to be routed and plumbed into the intake near the cone filter then. CORRECT?

also i have heard of alot of guys running check valves?

now are they running a check valve in this same hose from the valve cover or is it added to the hose on the driverside that connects to the intake that connects to the pcv valve?

some please answer my questions thanks

also where do you by a check valve from?

 

If ya got a blower then ya NEED a check valve in the line going to the PCV valve to KEEP boost OUT of the pan. If ya don't have one then your BOOST pressure is pressurizing the pan and causing oil to blow out EVERY hole it can find to get out.

 

so the check valve goes inside the hose on the driverside of the intake?