Ok, here is another set of answers on dry sump pumps. This is the last for
me I think. Enjoy..
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----- Original Message -----
From: "Bill Morten" <billm@petersonfluidsys.com>
To: "DrMayf" <drmayf@teknett.com>
Sent: Wednesday, January 29, 2003 12:49 PM
Subject: RE: Dry Sump Oil Pump Questions
> Dear Lawrence, thanks for all of the good! questions, but unfortunately,
> there is not accurate numbers for vague parameters, but i'll do my best to
> try to help. 1.) The horsepower to drive a drysup or wet sump pump will
have
> a lot of parameters involved, (i.e. viscosity of fluid, temp of fluid,
> ambient temp and flow rates. but to try to give you something to work
with,
> the numbers can range from 2 - 30 h.p depending what the extremes may be,
> the pressure section is by far the most consuming, as it is hydraulic
> horsepower demand. The scavenge sections have heavy loads and light loads
as
> the oil stream coming from the engine is not constant, there is a lot of
air
> coming with the oil stream, which varies the load. 2.) One advantage of
> having an external pump whether it is a wet or a dry sump pan, you can
vary
> the volume being delivered from the pressure section, with the speed of
the
> pump, and the clearance in the engine provides the restriction, to then
> build pressure in the system, with wider clearances, the pressure drops,
> with the same volume being delivered, and the pressure increases with
> tighter clearances, so given this understanding, we can then try to
> establish an oil pressure curve that looks alot like an RPM curve, and
only
> hitting the relief system. because once you hit the bypass, then at that
> point you are wasting hydraulic horsepower that could be used at the back
of
> the engine. so yes typically the load will stay relatively the same once
it
> hits that relief. 3.) when we test pumps on the flow bench, we shut off
the
> vacuum lines and read the amount of vacuum produce by that section, as
this
> gives us a efficiency bearing on that section, we typically see 21=22
inches
> of vacuum on a section, if it is sealed efectively, if we don't see
readings
> that high, then we know that there is an o-ring giving us trouble inside
the
> pump. Now as far as an engine seeing vacuum conditions will directly
depend
> on the homework done in the engine. you have to address bore/ring package
> sealing, this is the biggest leaker, all of the lip seals, front main,
rear
> main, cam if you have a jesel system etc, and to have all composite type
> gaskets so the engine is completely air tight. 4.) the power derived from
> the hydraulic load is based on the width of the pressure section and the
> flow rate at which you are demanding from that section. the position of
the
> pump does not matter. the big benefit of belt driving a pump off of the
> crank, is that you get rid of the load on the valvetrain.5.) no we don't
> have any graph's on power as you can make that graph read anything you
want,
> by changing the perameters, i.e. flow rates, viscosity, temperature etc.
so
> no we can't help you with that one. I hope i have given you a few more
> things to throw around, but the bottom line is that the dry sump system
will
> make power, how much comes back to the person manipulating the system, but
> it also gives stability to an engine that in a modern day race car has a
> tremendous amount of g force applied to the vehicle, subjecting the oiling
> system to very hostile enviroments and typically exposing the delivery of
> oil to crucial parts, and expensive parts, and allowing them to survive
> without dry conditions. the argument is do you allow folks to put
insurance
> on the money and parts invested and keeping fields of cars alive, or do
you
> go thru the process of exploded engines and continual bills, that most
can't
> afford once let alone 2 or 3 times, as the tire and chassis technology has
> brought to the platform of racing.I hop this is all recvd well, and if you
> folks have any other concerns or questions, please call me @ 800-926-7867.
> thanks, jeff
> p.s.- bill morten, passed away december 15, 2002. so please contact myself
> of Rod with further concerns.
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/// what is needed. It isn't that difficult, folks.
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