Science, not rocket

[QSHIPQ <QSHIPQ@aol.com>]

> Or we could look at a formula and plug in knowns, and explain Tshift with
just
> numbers.
>No, that is _exactly_ what we should not do.  This approach ignores the
>possibility that some of the assumptions are incorrect.

Like what phil?  By design of the Torsen 22/78/78/22 Tshift CAN be .56 * Trg.
That isn't an assumption sir, that is the physical design of the torsen.  What
exactly ISN'T right about that.  It's a Given, not an assumption.

> A center torsen, by design (that's physics) ...
>Nah.  As you're treating it, it's applied mathematics - the world of
>perfectly elastic collisions, no friction losses and no manufacturing
>tolerances.  Physics is a real world science that seeks to explain
>what really happens when the wheel hits the road.
>You are still treating the torsen as an ideal device.  You postulate
>transition from one ratio to another without allowing that it passes
>through intermediate states in finite time.
Sounds good.  Physics are a series of Laws.  We can take them and derive
Tshift.  I can plug in a frictional loss of 15% (which is really high) and
compute a major Tshift (we are talking about thousands of pounds of torque
here, 15% doesn't mean didley).  A Tshift can be Up to 78f and Up to 78r.  78
would be max, that's Tshift of 56% of Trg.  We can also say that an urq
understeers at 50/50.  So, 50-78f/50-22r is understeer.  Somewhere, by your
own admission we can have throttle oversteer.  I really could care less about
the transition, for physics it's irrelevent.  By physics of the center torsen
split, it CAN happen.  Does it?  Depends on some variables.  Same argument
with the 'bite'.  ALL the frictional losses and man tolerances add up to a
number, plop one in there phil.  In the numbers we are talking about here, the
term "significance" comes to mind.  Do the math.  Please, you might find it
enlightening.

Here some more physics for ya Phil.  Please correct my MATH not your
assumptions of it.

Drive wheel torque = flywheel torque * Gear Ratio * Final Drive * efficiency
(.85-.90 is mean here, doesn't matter insert whatever you want, I do .87 for
the audis, in fact high reading the available literature)
Trg = Flywheel torque * Gear Ratio

Tshift max % = (Tmax - Tmin) * .01

Tshift max lb/ft = Flywheel torque * Gear Ratio * Tshift max %

Wheel Thrust = Drive wheel torque/rolling radius

g force = Wheel Thrust/Weight

Helping you explain your 44 chassis vs. Urq 'bite' phenomenon, try this one

Weight transfer = (Weight * cg height/wheelbase) * g


The Laws of Physics tells us what is happening.  'Experiments' tell us what
variables may affect the chassis dynamics GIVEN what is happening.  Don't
confuse Physics with "experiments".  You want to deny the Physics.  I argue
you can't.  They are finite.  Happy to entertain your "experiments".  Driving
800km on a wet road hardly means much to either physics OR experiments.

Work a few equations Phil.  Do post up your MB numbers, I'm happy to do them
for you.  I need:
Rpm vs torque
Vehicle weight
Gear Ratios and Final Drive
Tire size

That's really all.  The rest is physics.  Sorry dude.

Scott Justusson
QSHIPQ@aol.com