pcv or evac:which is better for drawing vaccum?
#1
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Join Date: Jan 2005
Posts: 336
pcv or evac:which is better for drawing vaccum?
pcv from valve cover to intake or evac from collector to valve cover....what are the diffrences on a bbc with a single plane,dominator set up with a plate.my exhaust is free flowing(no chambered mufflers).
goal: to make cheap mans vacuum pump.....ideas???comments???thx in advance!
goal: to make cheap mans vacuum pump.....ideas???comments???thx in advance!
#2
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Join Date: Nov 2007
Location: Wisconsin cheesehead!!
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at WOT I would think header collector to valve cover would give more vacume. pretty much the same as how a carb works with Bernollis principle.
edit, at idle a pcv probably draws more vacume.
edit, at idle a pcv probably draws more vacume.
#3
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CRAFTSMAN
Join Date: Apr 2006
Posts: 54
Has anybody tried electric vacuum pumps? There's a guy on RJ selling them for $160. Unless I come across a deal at a swap meet for a mech. pump I will be running the valve cover to collector. I have a motor plate that might make mounting the mech pump a challenge.
#5
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Location: VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
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Use both at the same time.
By theory when one is open the other will be closed.
PCV is open only at times of high vacuum. Pcv is closed during full throttle. Crank evac system is mostly closed at high vacuum and is open when at low vacuum.
Ed
By theory when one is open the other will be closed.
PCV is open only at times of high vacuum. Pcv is closed during full throttle. Crank evac system is mostly closed at high vacuum and is open when at low vacuum.
Ed
#6
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APPRENTICE
Join Date: Dec 2007
Location: Utica Michigan
Posts: 16
This is the exaust setup I have:
Long tube headers > 3"-2.5" reducer > 2.5" H pipe > 2.5" delta 40's with 3" pipes going all the way back.
Now lets say I properly installed the collector evac kit and ran both of them to one valve cover and the other valve cover would have a hose running directly to intake vac. Does that seem ok?
Should I add a pcv valve, seporator, one way check valve?
http://www.racingjunk.com/gallery/profile/255255
Long tube headers > 3"-2.5" reducer > 2.5" H pipe > 2.5" delta 40's with 3" pipes going all the way back.
Now lets say I properly installed the collector evac kit and ran both of them to one valve cover and the other valve cover would have a hose running directly to intake vac. Does that seem ok?
Should I add a pcv valve, seporator, one way check valve?
http://www.racingjunk.com/gallery/profile/255255
#7
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Join Date: Sep 2007
Location: Montvale, VA
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Originally Posted by edvancedengines
Use both at the same time.
By theory when one is open the other will be closed.
PCV is open only at times of high vacuum. Pcv is closed during full throttle. Crank evac system is mostly closed at high vacuum and is open when at low vacuum.
Ed
By theory when one is open the other will be closed.
PCV is open only at times of high vacuum. Pcv is closed during full throttle. Crank evac system is mostly closed at high vacuum and is open when at low vacuum.
Ed
#8
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RACING JUNKIE
Join Date: May 2006
Posts: 2,044
The only thing I dont like about a pcv system is the oil vapors that are pulled into the intake plenum and intake ports valves etc, which leave nasty flow inhibiting deposits. Rather crap that junk out my exhaust and say adious.......
><Cp
><Cp
#9
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Join Date: Jan 2005
Posts: 336
i kinda agree with suckin into the intake tract oily fumes is kinda icky-is it a concern? if not,where to plumb into on my dart tall deck intake?by the way ive also got a nitrous plate kit on...what is opinions of electric vacuum pumps?if i just run evac to header is it ok to just use one valve cover lined down to one collector(cause i have air to fuel ratio sensor welded in one collector already)
#10
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Join Date: Dec 2007
Location: Utica Michigan
Posts: 16
:idea: So when is someone going to step up to the plate and get a patent on a AFFORDABLE electric or belt drive evac pump for the high performance street guys and become a multi millionaire?
I would do it but I dont have the funds to get it started
I would do it but I dont have the funds to get it started