Torque and diffs and... Agggghh....

[QSHIPQ@aol.com]

dave writes
>nope scott, you just don't see it.  you're misunderstanding what torque is.
>i'll say this one more time and then give it up as a waste of time, and
>bandwidth...
Thanks.

>torque doesn't (indeed cannot)  disappear in the ether.  with the locked
>centre, the output shafts cannot speed up relative to each other, so torque
>can and must transfer between them based on the tractive requirements of the
>2 output shafts.  and in the case of a wagging front wheel, 100% (read that
>again), *100%* of the torque goes to the back (less the frictional losses to
>the front end).  not 50%!!!  torque cannot disappear.  once again, with a
>locked centre 100% of torque can shift front and rear as and when required.
>with the open differential and all wheels on the ground, 25% of the torque
>is distributed to each axle.  regardless of the weight distribution (this
>doesn't happen with a locked centre and all wheels on the ground, but until
>you get the basics, there is no point in discussing that).  

Your terminology is changing.  That changes understanding.  I'll take a pass 
on comparing your former vs present posts in deference to WOB.  Using this 
same argument, torque from a torsen is capable of delivering 100% to the rear 
wheels too.  Not the definition of an LSD.  I think the confusion is in the 
definition of Bias Ratio and primary vs secondary axles and traction v 
torque.  With a locked diff, you aren't creating any additional torque, until 
that wheel lifts, in fact, you have one axle reducing engine Trg.  With a 
locked diff on the ground 50% of the torque is on each axle, by definition.  
Lift one *torque shift* is 50%.  Lift an open torque shift is 100%.  You are 
missing some basics in your argument.  

>open
>differentials reliably split 50% of the torque each way.  all the time.
No, if you take a turn in an open diff, where is the torque dave.  ALWAYS on 
the faster drive wheel.  100% torque shift.  That's not true of a locker.  
Take a turn, torque decreases as it shifts, in fact one wheel will apply 
braking torque to make sure, right up to total wheel lift.  Remember, all 
this *shift happens* before you lift a wheel.  Lift a wheel, all LSD act the 
same in terms of avaible torque to the ground, all opens act the same too.  
Again the basics are missing.

>even when one side has no traction.  when this happens, the diff will split
>torque based on the tractive force of the *least* tractive output shaft.
>the result, as orin has said, is the acceleration (increased speed) of the
>lifted wheel.

>i appreciate that this may be difficult for you, and that it is not what you
>have understood, but if you sit down with a piece of paper and draw it out
>it's quite obvious.  my offer for some spare time reading stands.  i can
>even scan some stuff and send it to you if you'd like....

Not necessary Dave.  I appreciate all your efforts to educate me and this 
list, but given the documented history here on this exact topic, and your 
"understandings", I'm not at all convinced that you have the basics in terms 
of differential application or BR or *torque shift* across a primary or 
secondary set of axles. 

Jeff and I had a phone conversation regarding our intentions to pursue this 
further.  Neither of us is all that excited about the energy required or 
potential outcome (Dave, you are trying to be civil, but it's not showing 
well:), another torsen thread we don't need, we all can agree on that.  :)

For further reading on BR, Torsens compared to open diffs, please read 
Chocholeks paper found on Jeff G's website:

http://www.mindspring.com/~audidudi/Torsen.htm

Further discussions can be referred to the archives.  Dan you can go back to 
sleep.

Respectfully

Scott Justusson
QSHIPQ@aol.com