Any need to alter the crankcase ventilation system?
Thread Starter
Burning Brakes
Joined: Oct 2001
Posts: 1,033
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From: Tracy California
St. Jude Donor '05
Any need to alter the crankcase ventilation system?
What are you guy's doing about your crankcase ventilation system's after heavy engine mod's "Cubic inches". Is the stock system suitable to reuse? My 400 used to allways sprang oil leaks and I've allways been suspicious about the PVC system.
Thanks
Thanks
Instructor
Joined: Apr 2001
Posts: 199
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From: Guyton, Ga.
Re: Any need to alter the crankcase ventilation system? (88-406)
I have tried running with and without a pvc, and you are right w/o to many oil leaks, and with I suck oil to the intake. right now I'm using a pvc valve for a 69 302 camaro motor, on the street it looks ok but haven;t checked the pluggs. going to the track next weekend for that try. QUESTION? has anyone tried using the breather evac. system from Moroso that welds into the header collecter on the street with any luck ?
Le Mans Master
Joined: Oct 1999
Posts: 9,713
Likes: 3
From: Sachse Texas
Cruise-In I Veteran
Cruise-In II Veteran
Re: Any need to alter the crankcase ventilation system? (88-406)
I am getting ready to install an evacuation system on mine because I am pushing oil out of the 2 breather caps I use. I have dismantled the stock PCV system because it would just eat oil. I have a few oil leaks because of the pressure. I should be putting it on in the next month or so.
Safety Car
Joined: Apr 2001
Posts: 3,525
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From: Houston TX
Re: Any need to alter the crankcase ventilation system? (MCAF84)
I use the Moroso system on mine. Just on the pasenger side. Works when the engine produces no vacuum (boost). Seems to work well. If you decide to do it with braided stainless (-12AN), I may be able to provide tips.
Aaron
Aaron
Le Mans Master
Joined: Oct 1999
Posts: 6,366
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Re: Any need to alter the crankcase ventilation system? (AKS Racing)
Where do you put the fitting on the engine?
A valve cover? would pulling from the lifter valley be a bad idea?
How are you going to set up yours vette92?
A valve cover? would pulling from the lifter valley be a bad idea?
How are you going to set up yours vette92?
Pro
Joined: Jun 2001
Posts: 697
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From: College Station Tx
Re: Any need to alter the crankcase ventilation system? (bill mcdonald)
AKS: I would be curious as to what kind of vacuum levels you are pulling - my experience with the header aspiration systems was that as soon as you introduced any kind of backpressure in the system you ran into problems (e.g. not open headers) - and that at low exhaust volume levels there was virtually no vacuum.
I have been running an electric vacuum pump on my car for about 2 years now and it has worked well. It pulls ~10-12" at idle, and 6-8" at redline (6800-7000). It is pulling through the valvecover. It has the additional benefit of excellent oil control (with respect to leaks) , as well as keeping the intake, etc. clean (from oil).
I have been running an electric vacuum pump on my car for about 2 years now and it has worked well. It pulls ~10-12" at idle, and 6-8" at redline (6800-7000). It is pulling through the valvecover. It has the additional benefit of excellent oil control (with respect to leaks) , as well as keeping the intake, etc. clean (from oil).
Safety Car
Joined: Apr 2001
Posts: 3,525
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From: Houston TX
Re: Any need to alter the crankcase ventilation system? (bill mcdonald)
I pull vacuum from the crankcase through the pasenger valvecover. I modified the original baffle to accept a nut on the inside just above the "accordian". I opened the vc opening slightly to accept a -12AN bulkhead fitting that had had the fitting inside the vc removed. Once the nut was inside the baffle, I simply screwed the bulkhead fitting through the vc, through the baffle housing, into the nut. I used a teflon washer on the outside. seals like a champ. As for the other end, I simply welded at the 45° angle per the instructions. They are interconnected with -12AN braided line, with a 90° fitting at the vc. I have checked crankcase vacuum, and I draw about 4" vacuum at full boost. I consider this is acceptable, because otherwise I would have no vacuum with the factory set-up. At idle and low rpm, I still have the factory PCV valve.
It seems to work on mine, for now. Time will tell.
Aaron
It seems to work on mine, for now. Time will tell.
Aaron
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Thread Starter
Burning Brakes
Joined: Oct 2001
Posts: 1,033
Likes: 0
From: Tracy California
St. Jude Donor '05
Re: Any need to alter the crankcase ventilation system? (ChrisB)
Chris
Tell us more about that electric pump. Does it run your brakes and etc...? whats it cost? and source?
Thanks
KM
Tell us more about that electric pump. Does it run your brakes and etc...? whats it cost? and source?
Thanks
KM
Pro
Joined: Jun 2001
Posts: 697
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From: College Station Tx
Re: Any need to alter the crankcase ventilation system? (88-406)
There are actually 2 vacuum pumps we use - the first one is the one I am using right now - it's actually a brake booster from an older model cadillac diesel. This one worked well on LT1's, but has had problems maintaining negative pressure on LS1's under high rpm conditions.
The new unit we are trying is actually a ford part - it is self regulated at 10-11" of vacuum, though we haven't had problems with either pump on over-scavenging.
Fitament can be an issue - it depends on if the battery is relocated, and if not what accesories are optioned on the car.
The pump does not run the brake booster, etc though the GM pump was actually spec'd for that and would have no problem. The ford unit being self-regulated would not be a good choice. The pumps can not be used for crank-case evac and brake booster operation simultaneously though.
Le Mans Master
Joined: Oct 1999
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From: Sachse Texas
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Cruise-In II Veteran
Re: Any need to alter the crankcase ventilation system? (Tomulrich)
Looks like I have some other options to look into. My exhaust guy was going to put one in, so I will ask him a few more questions about maintaining vacuum. I honestly would not have expected that it would be a problem though. I may just go with an exhaust ventilation and see how well it works, then go with an eletric setup like ChrisB if I run into problems. I wonder, could you possibly use the stock electric AIR pump for something like this? Mine is just sitting there doing nothing right now.
Drifting
Joined: Aug 2000
Posts: 1,316
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From: Houston, TX
Re: Any need to alter the crankcase ventilation system? (MCAF84)
What about mounting a remote oil filter adapter and pulling crank vent thru an oil filter to keep from pulling oil into the plenum?
