Thanks for your encouragement.  Last night I awoke

with the realization that

I gave you the wrong dimensions for my existing

restrictor orifice.  First

thing this morning I went to the hanger and checked

it.  In the reality of a

cool, winding Prescott morning, the actual

restrictor will just accept a #42

drill bit, so its about .093 diameter.

Let's see: .093 id @ 90 psi.............versus .065

@ 30 psi.  Surely

someone out there can compute this.  Is the pressure

and volume a direct

ratio?

The problem is the exact shape of the tiny hole can

change the flow greatly.

I think you are going to need to bite the bullet and

measure the flow. PL

Question #2:  How do I measure oil pressure inside a

turbo housing?  My

in-line restrictor is inside the L-bracket where oil

enters the turbo.

Good question. Probably not practical. Better to move

the restrictor

up stream. No difference in the flow but it is a lot

easier to measure

the pressure applied to the turbo bearings just before

the oil goes into

the turbo bearing housing after the restrictor. BTW I

wonder if the ceramic ball

bearing turbo's are this critical about oil flow and

pressure? PL

Seems to me that once the oil enters the turbo

housing the pressure will

drop off to some value near atmospheric, especially

if it then drains by

gravity to the oil pan.  In my present case, it is

being sucked by a

scavange pump at around 100 gph.

Any input anyone?

Tom Parkes

*********************************************************

Hi Tom;

You definitely have to bite the bullet.

In order to size the appropriate orifice I would need
either one of two (2) unknowns:

--Delta P (Pressure Drop across the orifice)
                     OR
--Flow of oil at the INPUT side of the Orifice

Flow is the easiest of both to optain, by either pumping
the fluid from the OUTPUT of the source pump into a
container, or by plumbing the inlet of the source pump
to a pre-measured quantity in the reservoir or
container. the thing to remember is to time the cycle
duration of either one as ACCURATELY as possible.
The rest is a piece of cake, you'll see.

Unfortunately I don't know anything about Turbos so I
couldn't even guess what the practical difficulty factor
would be. But, I do know this: "There's always a way"

                                Keep me posted,
                                    Butch

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