Vacuum pump
Thread Starter
Intermediate
Joined: Oct 2008
Posts: 30
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From: Concordia KS
Vacuum pump
I am in the process of installing a LS6 intake on my LS1. I changed out vent lines, moved the oil sending unit, and changed the valley cover to LS6 version. The LS1 intake was coated with oil. I have spent the day reading the pro's and con's of catch cans, air cap breathers, eliminating the PCV system altogether,etc. I have decided on an electric vacuum pump setup with catch can to avoid plugging anything into the intake. Does anyone on this forum have this setup? Who sells such a setup? Any input would be appreciated.
Tech Contributor
Joined: Jan 2007
Posts: 19,241
Likes: 1,091
From: Dyer, IN
I am in the process of installing a LS6 intake on my LS1. I changed out vent lines, moved the oil sending unit, and changed the valley cover to LS6 version. The LS1 intake was coated with oil. I have spent the day reading the pro's and con's of catch cans, air cap breathers, eliminating the PCV system altogether,etc. I have decided on an electric vacuum pump setup with catch can to avoid plugging anything into the intake. Does anyone on this forum have this setup? Who sells such a setup? Any input would be appreciated.
Thread Starter
Intermediate
Joined: Oct 2008
Posts: 30
Likes: 0
From: Concordia KS
).I'm trying to stay away from a belt driven vacuum system if I can (expense, messing with belts, etc) and go with something electric.
Tech Contributor
Joined: Jan 2007
Posts: 19,241
Likes: 1,091
From: Dyer, IN
Thanks for the comments... Not to rehash an already highly debated subject but it seems like there is no consensus on whether or not vacuum is needed to maintain oil stability (e.g. contaminant or water buildup) or seal integrity. Not sure whether I buy into the theory that you need a negative pressure in the crank case to maintain full ring seating but I do wonder about heating/cooling and air humidity causing condensation buildup in the crankcase (then again my degree is not in engineering ).
I'm trying to stay away from a belt driven vacuum system if I can (expense, messing with belts, etc) and go with something electric.
).I'm trying to stay away from a belt driven vacuum system if I can (expense, messing with belts, etc) and go with something electric.
I'm sure you'll find a good solution for you. Good luck.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
For those who have ditched the AIR system, Racetronix makes a kit that (electrically) converts the stock AIR pump into a vacuum pump. (You'd have to do the custom hose plumbing obviously).
Primarily intended for boosted cars, it comes with a pressure switch switch that turns on the pump anytime boost hits.
http://www.racetronix.com/product/RX-CEPH/RX-CEPH.html
For a n/a car though, this isn't a good idea as the stock AIR pump is not designed for 100% duty cycle, and the pump won't last long if run all the time.
But, coming up with an alternate switching device that activates it at WOT-only, or above a certain RPM, should be easily possible, and keep the pump duty cycle down.
As for being overkill, maybe it is...but maintaining crankcase vacuum at all times will benefit any engine, even on a lowly street car.
There's quite a few guys running dual catch cans, because the PCV flow reversal resulting from developed crankcase pressure at WOT on n/a cars is very real and has been proven over and over.
Might not be the exact answer you're looking for, but might give you some ideas too. Lots of people with AIR pumps collecting dust on garage shelves...
Primarily intended for boosted cars, it comes with a pressure switch switch that turns on the pump anytime boost hits.
http://www.racetronix.com/product/RX-CEPH/RX-CEPH.html
For a n/a car though, this isn't a good idea as the stock AIR pump is not designed for 100% duty cycle, and the pump won't last long if run all the time.
But, coming up with an alternate switching device that activates it at WOT-only, or above a certain RPM, should be easily possible, and keep the pump duty cycle down.
As for being overkill, maybe it is...but maintaining crankcase vacuum at all times will benefit any engine, even on a lowly street car.
There's quite a few guys running dual catch cans, because the PCV flow reversal resulting from developed crankcase pressure at WOT on n/a cars is very real and has been proven over and over.
Might not be the exact answer you're looking for, but might give you some ideas too. Lots of people with AIR pumps collecting dust on garage shelves...
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Your crankcase already has negative pressure, with the engine at idle remove the oil fill cap and you'll notice the RPM change, then put your hand over the hole and you'll notice it suck on your hand and the RPM will stabilize.
Thread Starter
Intermediate
Joined: Oct 2008
Posts: 30
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From: Concordia KS
The only pumps I have been able to find is the GZ version which is not rebuildable (concerned with duty cycle as this is a daily driver) and the Moroso version which is not a bolt on kit but has to be pieced together with brackets fabricated etc. If anyone is aware of any alternative kits please let me know.
Thanks for the replies.
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