[s-cars] Re: oil and turbos > CCV 201
QSHIPQ at aol.com
QSHIPQ at aol.com
Tue Dec 9 11:15:15 EST 2003
I don't believe in any stabilizers, I'd rather address the design of the
system that makes you feel the need for it. You have identified and moved the CCV
discussion to a related topic (tangental, but certainly relevent) of
different turbos on a given application and oil management in a more general sense.
One of the issues which can lead to increase CCV is not so much the oil feed,
but more the oil return. The turbo oil return line size is important in
designing a oil crankcase feedback loop that is of the least amount of aeration. I
might venture to propose that if a higher (different) feed pressure and flow
is used on a larger turbo, a larger feedback to the pan might be dictated. The
more pressure the feedback to the pan is under from a turbo, the higher the
aeration of the oil in the crankcase. Think of this as spraying water into a
bucket, but the release of aeration isn't so immediate. Aeration of oil is
extremely critical in the consumption of oil in extreme use enviornments.
Especially oil that has just passed thru a 1600degree heater core while performing
I'd also suggest Gary (if you already haven't done so) putting on as big an
oil cooler as you can fit on the car. Part of the "viscosity and thermal
breakdown" characteristics in oil is exactly because of aeration>saturation as oil
temps exceed the ideal temp (I consider oil ideal temp to be 100c)/viscosity
IMO, those tweeking S-cars into any significant number should minimally read
SAE 970922 (Development of Modern Engine Lubrication Systems), since it
applies directly to the I5 and audis "philosophy" on oiling systems. It can help
you as well Gary, since it speaks of the pressure/aeration/saturation issues of
oil in a general design sense as well.
No question in my mind that highly modified cars have to be micromanaged in
their systems and modified application (read: turbo) with regard to the
lifeblood of the motor = oil. CCV and PCV modifications and application really are
part of oil management, and should never be considered an afterthought. This
stuff is nothing new, and the problems with it now aren't any different. The
available catchcans may exceed my choice of plumbing fittings applied to a
drilled out chicken broth can I remember on my first SB back in the 70's, but the
reason for it is the same.
Scott "nerdman" Justusson
QSHIPQ Performance Tuning
In a message dated 12/9/2003 9:40:25 AM Central Standard Time,
gary.kaklikian at hp.com writes:
Yeah, I'm going to try the oil filler cap vent and Lucas Oil Stabilizer
first, although several 944t tuners suggest the oil feed restrictor with Garrett
turbos. No smoke out the exhaust, but the intercooler pipes are full of oil. I
don't doubt there's a problem with the oil rings, but compression is good and
leak down was under 10% on all cylinders. And oil consumption is only really
excessive on the track.
Any thoughts on using Lucas Oil Stabilizer, with synthetic or dino juice?
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