[Shotimes] Re: PCV extractor and vacuum in crankcase

[Paul Nimz]

You know they make Vacuum regulators for cheap.  They are called PCV valves.

What I would do if I was in fear is put a 4 cylinder PCV valve on the front
cam cover connected backwards so fresh air is being drawn into the cam cover.
Attach to this the ricers small air filter of choice.  Then install a tee in
the line going from the oil separator to the exhaust piece.  Attach a vacuum
gauge to this and go hot rodding.

Only then can you tell if you have too much vacuum.  I consistently run 8-12 "
Hg of crankcase vacuum but under light load conditions and at WOT  0" Hg.
This mod that you are doing will do the opposite.  It will create the highest
vacuum with the increased exhaust flow.  I would look for 15" Hg at peak for a
goal.  The higher, the better and you should see a very reduced reading most
of the time.  It is only at WOT that the high vacuum will be present and
strongest.

At WOT there is also the greatest creation of blowby gasses too.  This will
mitigate the high vacuum levels to a certain extent.  But this will be offset
by lessening the blowby by sealing the rings better because of the high
vacuum.

Paul



On 8/1/2005 8:09:23 PM, van Oss (vanoss@centurytel.net) wrote:
> I am a faithful disciple of the apostle Paul [Nimz].  Yet verily, he hath
>
> struck fear into my heart.  Paul and I have been talking about installing
> a
> PCV extractor kit on my 92.  Basically it uses a pipe welded into the
> cat-back at a 45-degree angle (venturi effect) to draw crankcase fumes
> into
> the exhaust stream.  Crankcase vacuum makes a little HP (thank you,
> Smokey
> Yurick) and safeguards the intake air plumbing from automotive emphyszema.
>
>
> The question is whether to close off the opening in the front cam cover,
> to
> generate max vacuum.  If so, words like "collapse some seals" test my
> faith.
> Do I just drive around and see if my front and rear crank seals implode?
>
> Ah, once again VO gets to experience the bleeding edge of innovation.
> Smokey, where are you when I need you?  Bet
> he's not answering emails.
>
> VO
>
>
> ----- Original Message -----
> The noise is from air leaking past the seals and TB openings.  When I did
it
> to the V6 it developed a whistle.  It may collapse some seals but I don't
>
> know.  You could add some flow at the valve cover with a filter that is
> restricted if the vacuum is too