Anything wrong with venting crank case vent to atmosphere?

[Jon K]

Read topic. If you're not sure, please don't answer, trying to finalize some stuff up.

[Anthony (M5 in Calgary)]

Bad for the environment 'cuz you're pumping HCs into the air.

Bad for the engine unless you install a draft tube like they used in the early '60s. Essentially a tube with an angle cut at the bottom, inserted into the air stream. Air passing by created a slight vacuum to pull out blow-by components. Your oil life will suffer.

HTH,
Anthony

[Jose]

No problems at all, just the enviromental thingy. A lot of BMW trackers also use open ventilation, nothing wrong with that. Oil life will not suffer if you use a crankcase filter on the end of the tube as this will prevent junk etering the tube. Just keep a closer eye on your oil level. The only downside I could think of, warm oil smell could get into your interior due to the open system.If you want it, get it.

[Jon K]

No problems at all, just the enviromental thingy. A lot of BMW trackers also use open ventilation, nothing wrong with that. Oil life will not suffer if you use a crankcase filter on the end of the tube as this will prevent junk etering the tube. Just keep a closer eye on your oil level. The only downside I could think of, warm oil smell could get into your interior due to the open system.If you want it, get it.

Well, i was reading that this will cause positive crank case pressure? Something about hurting main and rear seals? Any insight?

[Jose]

Do you have An M50 or M30 ? The M30 is very sensitive on changing the vacuum routing ,the M50 has completely diffirent system. I know a lot of guys I know use a catch tank for the crank ventilation as they have no other option and it' s a trackrule to be able to compete. I' ll check with them tomorrow, to verify the bearing issue. I' ll keep you posted.

[Anthony (M5 in Calgary)]

Well, i was reading that this will cause positive crank case pressure? Something about hurting main and rear seals? Any insight?

you couldn't get positive pressure within it. I'd disagree about no issues with the oil though. The way the factory sysem is set up, a contolled vacuum bleeds crank gases into the inlet system to purge the blow by. With an atmospheric vent you'd get much less circulation as the pistons would just be moving the vapours around inside the CC.

My $0.02CDN.

Anthony

[Jose]

I can see the meaning of your point Anthony, but I really doubt it would make that big of a difference. I have a car fitted wit a 2 L 16 valve engine with 48 mm Webers on it and this engine has a K&N CC filter on it and it' s amazing how much fumes this puts out. I think there is enough pressure to push the vapours out anyway. It' s hard to say if the engine will suffer damages due this change in the vacuum system. Tomorrow I' ll check with the trackers. They take their engine apart each month so I hope they can help us out a bit. Thanks for sharing your view.

[632 Regal]

since your engine is designed to be a "sealed" system it will probably mess up the idle and running quality, maybe even throw a bunch of codes.

If you are thinking about this in order to control the blowby issue you will have with the supercharger than I would do something a bit different.

I dont know how much blowby the boost will make and the pressures involved with it either. The racecar used to make a tremendous amount of it and simply putting 4 breathers on the valve covers failed so I ran 2 lines down into the collecter part of the hedders which served 2 purposes. When the engine would smooth out over the obnoxiously large cam at about 4ooo rpms it pulled a vacume kinda like a pcv does to get vapors out and at full throttle the draw helped pull the blowby out and it stopped popping gaskets.

With your engine being a fraction of the size I would still run a sealed system but would somehow have a valve connected to the valve cover or wherever you add oil. Make the valve so it would self close but open with positive crank case pressure. Make it large enough so that it will actually release the pressure not like a little 3/8 hose but larger. And yes it will blow oil out too so you could run a hose into some kind of catch can.

I hope this makes some sence to you cause I'm having a real hard time trying to describe myself here.

[632 Regal]

Well, i was reading that this will cause positive crank case pressure? Something about hurting main and rear seals? Any insight?

it shouldnt cause a positive pressure if its vented. if its sealed with no breather or pcv system it would,

[Robin-535im]

I'm really not sure. Wait - what was the topic again?