Crankcase Ventilation
 

Any thoughts on this subject for Stock Eliminator applications?

Re: Crankcase Ventilation
 

Ya, put a dry sump, and vac pump on. Just don't get caught. No, seriously, someone who actually knows the answer will chime in.

Re: Crankcase Ventilation
 

Good ring and valve cover seal with a sealed crankcase breather, and its worth it on my car. There is a thread about vacuum check valves, that is worth searching for.
Sean

Re: Crankcase Ventilation
 

I can only pull a vacuum in the crankcase by using manifold vacuum. When things are right, I can get about 6" of negative pressure. If I just use the headers, I get no movement on my vacuum gauge. I recently discovered that my oil separator breathers weren't getting all the oil out of the vacuum line to the carb. I could see some oil residue on the carb gasket under the carb (see picture 2). I'm hoping a vacuum pump style separator will cure the problem. I use the old Jenkins/Moroso pan evac system. Does anybody still use this system?
[IMG]http://i246.photobucket.com/albums/g...eCapitol-1.jpg[/IMG]
[IMG]http://i246.photobucket.com/albums/g...sket4500-1.jpg[/IMG]

Re: Crankcase Ventilation
 

I've seen engines with a shop rag taped around the valve cover breather tube. What's up with that?

Re: Crankcase Ventilation
 

Engines with lots of blow by build pressure in the crankcase and if there's enough, a mist of oil will be pushed out of the valve cover breather. The rag was supposed to catch the oil. I haven't seen that done for many years.

Re: Crankcase Ventilation
 

I played around with a vacuum balance system on my stocker back
in 1975. Bill Jenkins was experimenting with it and the guys at SRD
who were neighbors ,were selling some of the components to make
systems. I still have some of the origional parts that I got from SRD.
I ran a vbs for a short time ,but I never really gave it a good test.In theory
they are supposed to improve H.P. ed

Re: Crankcase Ventilation
 

How about the use of PCV Valves?

Re: Crankcase Ventilation
 

I assume you meant Super Stock? Stock Elim. was very restrictive back in '75.
I doubt you would have gotten away with anything more than an OEM type PCV back then..
Unless you were just using a Stocker for testing purposes ?

Re: Crankcase Ventilation
 

What I'm personally attempting to gain and learn from my initial question, having very limited knowledge of the subject in general and it's application to Stock Eliminator rules is, what is the current set up for the heavy hitters?
Also why does N.H.R.A. not allow valve cover breathers to be evacuated into the header collectors in Stock?

Re: Crankcase Ventilation
 

I didn't think a PCV valve would remove oil vapor from being sucked into the manifold.

Re: Crankcase Ventilation
 

Frank, always use a PCV. It helps to keep some of that expensive light weight oil inside the engine..(No rags needed)
I doubt you would still pull any vacuum at the end of a run though.That's why you need the header hoses and valves.
Of course,..not legal in Stock

Re: Crankcase Ventilation
 

Thanks Mark.

I found this image; http://www.aa1car.com/library/pcv.gif

My primary interest in this subject it to maximize ring seal and of course not waste any of those valuable shop rags!

Re: Crankcase Ventilation
 

I wanted to try an old style road draft tube. Never got a chance. Of course it wouldn't do anything until you're moving, but I thought it might be worth experimenting a bit.

Re: Crankcase Ventilation
 

how about a brake booster check valve for vacuum and ventilation???

Re: Crankcase Ventilation
 

Mark, I ran it on a 72 Camaro 350ci 4bbl Q-j ,In H/Stock. Anyway I used a std PCV valve on the one side with all the
other openings closed up and on the other side I used an anti backfire flapper valve that I got from SRD, there were no openings in the system
and the crankcase would hold a good vacuum at idle . I did not and could not run hoses to the headers. This may not have been an optimum
system,but I did experiment with it a couple of times. From what I remember I didnt see any improvement ,that didnt mean it didnt have potential though. ed

Re: Crankcase Ventilation
 

I tried the hoses to the collectors at the track (not this car) when that stuff first came out. Never found a thing. I tried a slick little check valve with two PVC valves and a closed crank case on the dyno. Pulled good vacuum to about 5000, then it went away. No pressure as high as we were pulling it then (7700) but no power gain. Finally went to one PVC on one side, and a breather on the other. It's a legal vacuum leak, so you may as well use the highest flowing PVC valve you can find. LOL No more condensation in the valve covers that time of the year either. Didn't back-to-back-to-back it, but appeared to be a couple above 8000. Guess it depends on how well yours would like a larger TB.

Re: Crankcase Ventilation
 

Late 60's-early 70's GM Power brake check valve on the valve cover & then hose to the intake manifold and DO NOT forget to turn the main seals around!!!-- FED 387

Re: Crankcase Ventilation
 

I tried a road draft tube on my 340 about Fifteen years ago and first race they
made me pull it right off!!

Re: Crankcase Ventilation
 

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

Re: Crankcase Ventilation
 

I guess it depends on the year of the car? What was the last year they used them, '66?
Anyhow, I thought about that after I posted that. Our car was a '71, so I guess it wouldn't have been legal, either.

Re: Crankcase Ventilation
 

Yes, yes it's all comming back to me now ! Was that for the single ring piston that was being experimented with. I believe one of my friends went to a Manley seminar back then and thought this new style ring ,piston combination was going to be " to die for" ed

Re: Crankcase Ventilation
 

That would be 1962 Fed. and 1959 Ca. I believe

Re: Crankcase Ventilation
 

It's hard to see in my photo, but the brake booster check valve is there. I've run the seals backward but didn't see a gain in vacuum on the gauge. I was recently told that the seals only needed to be turned when using a pump. If I install a puke tank designed for a pump, do you think it would fix my oil in the intake problem?

Re: Crankcase Ventilation
 

Yikes! I are getting to be an old fart. I remember seeing cars on lifts that while running, you could see the smoke billowing out of the tube. I guess '66 was wishful thinking.
It's ironic though, the stuff that's allowed these days, and you show up with a draft tube and yer out!

Re: Crankcase Ventilation
 

Me to, for every stroke you could see a little puff of smoke from the draft tube. ed

Re: Crankcase Ventilation
 

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

Re: Crankcase Ventilation
 

would love to have some feed back or "hint" on the correct brake booster check valve!!!!......late 60's???.....early 70's????......I need this junky 275hp 327 of mine to pick up!!!!:D:confused:

Re: Crankcase Ventilation
 

The brake booster valve I'm using is a 1970 GM version. It just allows air to go in one direction. I don't know why one would be more beneficial than another, but I'll look into it.

Re: Crankcase Ventilation
 

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

Re: Crankcase Ventilation
 

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

Re: Crankcase Ventilation
 

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

Re: Crankcase Ventilation
 

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.

Re: Crankcase Ventilation
 

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

Re: Crankcase Ventilation
 

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.

Re: Crankcase Ventilation
 

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.

Re: Crankcase Ventilation
 

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?
http://i246.photobucket.com/albums/g...ck/panevac.jpg

Re: Crankcase Ventilation
 

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.

Re: Crankcase Ventilation
 

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 !!!

Re: Crankcase Ventilation
 

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.